Even if the victim is a fault, partially or wholely, victim blaming, per se, is still a logical fallacy when it's used to support a claim.
Not if the claim being made is that the victim is partially or wholly at fault or is a claim that would be logically supported by the victim's responsibility. You are essentially saying, "victim blaming is a logical fallacy when it is a non-sequitur." In that case, its fallacious nature lies in that fact that it is a non-sequitur, not in the fact that it is victim blaming; there is no additional explanatory power to be found in the fact that it is blaming the victim.
That's like saying an ad hominem is only a fallacy when the source is actually not reliable. (It's still a fallacy). Or that an argument from authority is only a fallacy if the authority is wrong. (It's still a fallacy.)
Victim blaming, whenever used proof or an assumption without specific proof is a fallacy. A claim is not a fallacy. You can claim someone is a liar, but, unless you're suggesting that makes his argument false, it's not a fallacy. You can claim that someone is an authority, but unless you argue that makes his claim true, it's not a fallacy.
Logical fallacies are associated with what proves an argument to be true or false. If some form of argument (victim blaming, ad hominem, argument from authority, hasty generalization) is not being used to proves something, it's not a fallacy.
Victim blaming does not prove an argument about responsibility for an event, so it is always fallacious. It is not proof that the victim was responsible, no matter what responsibility the victim has, but one can make an argument that a victim in a specific situation has some responsibility without using the victim blaming fallacy.
I only jumped into this conversation because I don't like the way so many things are called logical fallacies when, they are just claims or arguments.
Logic is used to show proof of a claim being true or false. A fallacy is a logical argument that does not constitute proof. In this case, victim blaming, in an of itself, applied to a specific case, a class of cases or a group of cases does not constitute any proof at all, and thus is a fallacy if used to prove blame. But arguing that, for specific reasons, a victim bears some responsibility is not a logical fallacy.