Someone can have misplaced gratitude, that is, misplaced acts of gratitude. You can also have misplaced compassion, misplaced generosity, misplaced honesty, misplaced respect. When we look at all of the cases, a pattern starts to result:
(1) In these 'misplaced' cases the virtue itself is fine. That is, misplaced gratitude is the act of gratitude; even if your gratitude is misplaced, it can express a genuine virtue of gratitude. You can acquire the virtue of gratitude by acts that include misplaced acts of gratitude. Something is wrong with the act, but the acquired virtues are unaffected.
(2) All of the relevant cases seem to be closely tied to what St. Thomas calls the potential parts of justice. You can occasionally make a case for misplaced acts of virtue from some other region of the realm of virtue (misplaced caution, perhaps, or misplaced patience, or misplaced docility), but I think when we look at such cases more closely, we will always find that a potential part of justice is always involved somewhere. I think we can actually rationally prove something like this. By the very nature of the case, misplaced acts of virtue require two things:
(a) An identifiable standard of right action: They need this in order to be misplaced. There has to be something to distinguish the misplaced and the correctly placed.
(b) A latitude in how this standard applies: They need this to prevent the misplacement from making the act inconsistent with the virtue.
This is exactly the profile of potential parts of justice, which are virtues that (like justice) have a standard of rightness based on what is in some sense due but (unlike justice) have a looseness in the debt or in how it is paid. Gratitude, like justice, is in some sense a rendering of what is due: it can be misplaced. Gratitude, unlike justice, doesn't make things even: thus there is no exact standard that it has to fit. Because of this combination, we can have misplaced gratitude: gratitude in cases where we are not getting what's due right can at least sometimes still be real cases of gratitude.
This would also explain, of course, why it's difficult to make sense of 'misplaced justice' in a sense where the justice would still be genuinely just. If you aren't actually contributing to making things even, you're not meeting the standard of justice. Justice has fairly strict and exact standards, and the misplacing the act means that you are no longer meeting them, however well intentioned you might be.
(3) I said before that I think that in non-justice-family virtues we only get misplacement if a potential part of justice is involved. Virtues can 'command' acts of other virtues. (The same is true of vice.) For instance, you could, out of gratitude, sacrifice to God; then the act of the virtue of religion (sacrifice to God) is also, as if it were an instrument, an act of grattitude. So when a virtue annexed to justice 'commands' another virtue, it introduces the above conditions, and misplacement becomes possible, because the non-justice-family virtue is acting as a sort of instrument to the justice-family virtue.
(4) Do all potential parts of justice allow for misplacement. St. Thomas gives the following as virtues annexed to justice as if they were potential parts:
religion
filial piety
observance (respect)
truthfulness (honesty)
gratitude
vindication
liberality (generosity)
amiability
Of these, we've already noted that you can obviously have cases of gratitude, honesty, generosity, and respect.
Vindication is trickier, because it is the virtue concerned with punishment, and misplacement of punishment could very well be unjust, as one of the key components of justice is not to harm. Obviously if every misplacement of vindication involved injustice, misplacement would not be possible here. However, I don't think this is the case. I think there are genuine cases in which punishing the wrong person as an honest error, while obviously a defective act, could very well be consistent with the virtue. But perhaps it's easier to think of the misplacement not in terms not of persons but in terms of punishments, in which one could apply the wrong punishment in a way that does not involve acting viciously. Misplaced vindication may be rare, but I don't think it's impossible.
The three best candidates for potential parts of justice that do not allow misplacement, then, are religion, filial piety, and amiability.
Religion obviously doesn't allow much room for misplacement, because misplacement gets you easily into idolatry (if you misplace by worshipping something other than God) or undue worship (if you misplace by worshipping with the wrong kind of worship). In a sense, the seriousness of worship squeezes out most of the room for misplacement by introducing a higher strictness of standard. In a sense this is what justice was doing with vindication: it was introducing a stricter standard of what is due that could cause problems with misplacement. Since here the stricter standard is part of the virtue itself, rather than another virtue, there's even less room. Nonetheless, it's perhaps just difficult to have misplaced religion that is still virtuous religion, and not absolutely impossible. Think of Emeth in C. S. Lewis's The Last Battle, for instance.
Filial piety is a candidate for much the same reason as religion -- it involves a stricter standard of what is due. If religion can be misplaced, then obviously filial piety could, in principle, although the reverse is not necessarily true. The distinctive difficulty with filial piety is that it's harder to think of how misplacement would work. Filial piety is respect for parents, but the way it works extends to others -- you can have acts of filial piety to people who are not literally your parents. Obviously you can have them to any of your ancestors, but also to those who are in a parental position to you for some other reason, and to people and things who are associated with your parents in a way that concerns filial piety. So merely extending acts to people other than parents is not misplacement; if we are thinking in terms of other people, it would have to be people who have no parental association with you at all, and it's difficult, although perhaps not impossible, to think of real-world cases. But perhaps again we should think of it not in terms of different people, but of acts of filial piety toward parents (or parental figures) that happen to be inappropriate for some other reason -- for instance, we could perhaps talk of misplaced piety in cases where a child is giving a parent the kind of respect that would ordinarily be right, but is not appropriate because of (say) sexual abuse.
Amiability, or friendliness, is in some sense at the opposite end. Religion and filial piety are candidates because they are most like justice in terms of strictness of what is due; they differ from justice primarily in that there is no payment adequate to making things even. Amiability on the other end is the potential part of justice that is least like justice in terms of strictness of what is due -- it has the most latitude of all the virtues annexed justice. You can think of it in terms of a kind of debt -- you owe it to people try to be friendly -- but that's so loose a sense of debt that one might think it merely metaphorical. That there is some kind of connection with debt, however, is perhaps more obviously seen negatively: if you treat people in an unamiable way, you have treated them in a way that they do not deserve. Nonetheless, this is quite loose. This might make one worry whether we then would still have enough of a standard to allow the misplacement, particularly as we owe our 'debt' of friendliness to everyone -- i.e., we owe it to everyone to act in such a way that we ourselves are not shutting down all possibility of genuine friendship. Nonetheless, friendship is not anything goes, and it seems you can very well have misplacement in the same way we suggested with filial piety, but even more easily: your act of friendliness, while consistent with the virtue, can be the sort of thing that would ordinarily be appropriate, but is not in the case due to some extrinsic reason.
Thus I think it is in fact true that all potential parts of justice allow misplaced acts of the virtue, although in cases where there can be additional strictness, either due to the matter of the virtue or due to interaction with some other, stricter, virtue like justice, it can be more rare because more difficult.