I am traveling on 2 separate PNRs, one HKG-ORD in CX J. And then 8 hours later onward from ORD-LGA to YUL in Y.

Will I have lounge access while in ORD? I know if I was traveling in Y and connecting to international J I would, but it's unclear to me on the AA website for my situation.

[EDIT]:

Actually based on the one world website it seems like I am allowed access.
http://www.oneworld.com/ffp/lounge-access

However then my question goes... My International flight arrives in Terminal 5 but my domestic flight leaves 8 hours later from T3.

Is there any way to go back into the BA lounge at T5 after clearing immigration? Or is my only option to access the terminal 3 admirals club ?