Could another suggestion be staging 1 dedicated lounge car and dining car in Spokane to be added to the trainset.
Well, that is a problem. They are very short on Sightseer Lounges. Even if all non-wrecked SSLs were returned to service they just might have enough to cover all Superliner LD trains. They are also somewhay short on unmutilated Superliner full diners.
I'd much rather see SSLs return to the Eaglet and the Capitol. It also would be nice to have protection SSLs at Chicago and LA if there were any at all left after equipping all trains (and allowing for maintenance rotation of them).
They have a few unassigned mutilated Superliner diner/lounges around, IIRC
Whether they all have been brought back to roadworthy condition after COVID mothballing is another issue. Those have a full Superliner galley and have the capability to provide full dining service.
Staffing could prove an issue. Portland does not have an OBS crew base. 27/28 are crewed out of Chicago OBS base. 7/8 are crewed out of the Seattle OBS base. That is a surmountable problem. Perhaps a Seattle crew working a Cascades, then working east and back on 28/27. The chef/food specialists still present a problem, though.
I do not know what OBS crew arrangements were considered when the Portland diner/lounge proposal was on the table, or if it even got far enough that someone was tasked with working a stafffing proposal out.
In any case, a Portland diner/Lounge would avoid running into very hard limitations on equipment, and provide most of the capability needed (except the SSL's big windows).