Well, he had pulled at least one trick which I thought he could use currently, so he may be still with us.
BTW, that's another reason we had to attack Fomors - they are too tricky!
I also noted some strange behaviour of the game in our part of the world - some of my armies hadn't move as ordered & probably his didn't, too (I can't know for sure whether he ordered them for the reason you just mentioned). But this is another question completely. Did you try to PM him?
As for advice I consider it a part of cooperation. It's fine to share it, but it IS a behavour of an ally (not one very forthcoming with his help, but still). So I see no qualitative difference between trade, actual subsidies or advice. THe latter is harder to prove, certainly, though...