Your dad's AS flight will arrive into ORD T3, and his QR flight will depart from T5. Once he lands in T3 he can access any of the AA Admirals Clubs, just needs to show his QR ORD-DOH business class boarding pass.

With an 8 hr. layover, whatever he does tell him NOT to go directly to T5 when he arrives at ORD. Go use the Admirals Clubs in T3 until about 2 hrs prior to his QR flight, then head to T5.

Going from T3 to T5 requires exiting security, taking a quick train over, then reclearing security. As mentioned above the lounges in T5 are awful, you want to spend as little time there as possible.