Putting 2 + 2 together, I come up with this: Amtrak is the landlord of CUS. Third party operator of Legacy Club pays Amtrak rent; in return, Amtrak also provides staffing.
The point of the Legacy Club--it's an advertisement for the future CUS. It shows what the station can be once all the hidden spaces are opened up, renovated, and brought back to their former glory, as Amtrak solicits proposals from retailers, service and food operations.
In this interpretation, the Legacy Club isn't so much a passenger facility as it is a prototype--a showcase for prospective commercial tenants in the new CUS. Get on board, guys, build something like this for the captive audience at CUS, and prosper.