林肯 Lee seemed to know Nick (from our universe), how do 你 think they know each other?

I don't remember their interaction very well, but I don't think they knew each other

Difficult, I guess that there also was a Nick on their side

when they all crossed over to the other side to rescue peter...when nick was on the bridge dying, agent lee 说 "nick?", not sure how he knows him, but i'm guessing he obviously knows the one on the other side (meaning his side)