Apologies for another annoying access post!

Flying F from IAH today, I’m flying via DFW so AA J IAH>DFW then F DFW>LHR, friend flying direct IAH>LHR about four hours later that evening. I’m aware BA have closed lounges in IAH but friend and I will be arriving at IAH at the same time (currently finishing road trip together), will I have fast track security and will I be able to guest him through that? Will I be able to access AA Admiral’s Club lounge (I know it isn’t great) on back of my DFW>LHR F ticket (I believe so as that is my longest segment but not quite sure if AA adopt the same access policies as BA) and be able to guest him into there?

Many thanks!