I'm not sure that I'm following you on this. You mean that you actually stopped at a Volvo dealership, an EXPERIENCED tech (NOT their lube kid who lacks knowledge, experience) actually heard the noise, said "YEP, input shaft bearing" (which isn't likely mind you), THEN the SAME experienced tech (hopefully a Volvo Master Tech?) actually then said that the same noise he previously heard and diagnosed in a second (standing outside your car before) is now normal after the car stayed there for two days?

I can understand a possible throw-out bearing but not both that and a trans, input shaft bearing too (which one wouldn't just jump to concluding in a split-second driveway diagnosis "shooting from the hip"). One would take a little more time than that to properly diagnose that as that technically means a new (reman. trans) if warranty as no one does trans overhauls anymore in Volvo dealers.

IF that's true, THEN go back and talk to the service manager and explain this story to him as if the tech who initially "diagnosed" the noise as being a real problem then says "normal", one needs to get THAT tech involved. You need to take the service manager and their Master tech for a drive (if required to hear the noise?), say "THAT NOISE"...."WHAT IS THAT NOISE?" and see what they both say about it, normal or not?

Contacting Volvo might help but you'll also be adding another cog in the works. You should be able to get the dealers service manager to explain this situation to you first.