Tips are just added to what you made so yeah, it counts wherever an hourly wage counts.
However the current system just gets people not to report tips, so realistically they’re paying a lot less into SS anyway. It’s basically just the government going “alright let’s make that official instead of tax fraud”
Shuffles by one if it has to, but anyone with a boss can just be replaced because that higher authority exists.
Usually this is discussed with just the president, who has no higher authority, or in the case of mass death like nuclear war, with an assumption that we lose a good chunk of the government. But not this conversation, where VP matters more than P for certification.