TBH I'd go with it not being on him at all. If as someone said (Louise Mench?), it was on a Russian bank server in the building, then it wasn't even anything to do with him.
Idiocy to tweet about it in any circumstances; special points for doing it before he knew what it was even about; bonus if he did and was in fact warning associates.
I've been chatting a little bit with some Trump fans on Twitter (not long conversations, or necessarily representative of all followers of course, although one interesting DM chat in particular). But it's interesting.
Some think it's genuinely smart that Trump's not releasing his taxes because they think he'll just be nitpicked and attacked, and they don't see the point. That he gives them hope for the first time in a long time. That Russian connections have already been investigated and dismissed by FBI. That it's good he's not acting like a normal politician. They're also seeing their leader attacked in what they think is an unreasonable way. And themselves too for daring to vote for him.