Haven't knocked out the details of it just yet, but Wash knows specifically of Natasha on the other side and has tried to reach out to her to contact her. The plan's currently for Wash to end up running into her at the village whether they manage to arrange that somehow or through Convenience or something, and after he does make contact with her and they work out a way for Nat to drop info off to him safely, Wash will go straight to Piotr about it. And maybe annoy him because Wash didn't go to him beforehand, but uh, he'd be able to show him some well planned out incredibly meticulous caution?

I also know Kaidan mentioned wanting to be an informant and Wash doesn't know him personally but I'd be super down for them being in contact eventually somehow through Nat or other means, I dunno. Might work better with someone else though since Wash will have Nat already!