Alan B, thank you for the tip, I will make sure that we are in Business, thats a nice little side effect!
I have a couple hours in DC, might take a stroll out of the station, is there a way to stow our luggage in the station? I know that this varies from station to station.
Yes, you'll have to show those sleeper tix to the attendant in Philly to gain access along with the tix for the Regional, but you entitled to use both clubs. Your sleeper stubs will also get you into Chicago's Metro Lounge if you have need to hang out there for a while too.
Also note, you should be booked into Business Class on the Regional, so be sure to verify that with the agent after completing the reservation.