Lots of info here but my guess is it's a Dometic issue. There are LOTS of them that just go bad lately. Seems with the new models they used a thinner metal for the coils and it rubs and leaks out.
Happened to us this year - brand new unit, on the 4th trip it started going and by the 5th it was done. Compressor would run, fan would run but in the shade and 85f it was blowing 75f air at best.
Diagnosis - bad unit. Not voltage, not wiring, nothing but lost refrigerant. There are guys in the Open Range forums on their 5th Dometic in a couple years! Luckily we bought the extended warranty so when it happens in years 3-5 we're covered.