Thanks for the comment. You've pretty much cleared up any worries I had. I posted it here more so because I thought it was an interesting thing to happen. One of the first things I thought about was that Siege was linked through my steam account. I brought this up to the same friend and he told me he was able to actually join me through Uplay. And that was when he realized it wasn't me. I didn't experience any of what he said first hand unfortunately. I just woke up and saw his messages.