Sorry but your tech is wrong about the 322 code meaning "needs new trans" as that's simply wrong. That code CAN indeed be one that yes, can mean "PNP" switch as well and I've seen it duplicated several times before by using Volvos dealer VST (scan tool).
That code can also mean bad S1, S2 solenoids in the valve body (was the original thoughts on it) and they too can be replaced w/o slamming you for a reman trans. In recent years however, that code has been cured with a new PNP switch.
more.............? There's a Volvo SB on proper diagnostics for '95 850 trannies ONLY as that year did have some trannies with a few known problems but for the 322 code appearing only, it's cureable.

Was your "trusted indy tech" ever at any Volvo factory training for 850s, like an ex dealer tech or does he just talk alot?

As for AC problems, it's an old issue here discussed often and your car is also an old model year so believe it or not, the newer Volvos are no longer having the same Evap problems but if your tech followed correct proceedure, AC dye should have been added to actually see where it's leaking from the Evap rather than guess. By Volvo, there's also a new "kit" of several parts besides the evap that's suppose to (hopefully) keep the replacement evap from failing again but it's also more $$ and most customers don't opt for it even when informed that it should last longer than the original.