I don't think that's accurate.
If AA emerges with six year contracts in place, and then purchases or merges with US, then won't the workgroups have to re-negotiate combined contracts, like they've been doing at UA-CO? If not for the USAPA fiasco, wouldn't the US East and West pilots have negotiated a new contract after the merger of US and HP? When DL and NW merged, DL negotiated a new joint contract with the pilots at the very beginning. Your post makes it sound like all US employees would simply be forced to work under AA's contracts if AA buys US after bankruptcy, and that's not correct.
Wings396 might be thinking about the passenger service agents at US having to fall under the non-union upper management say. When all is said and done after everything has been discussed and considered the USAirways passenger service agents might be outsourced or working for express pay benefits and work rules like at a lot of small and medium stations at AA