2 zones 1 thermostat or 2 thermostats?

Are you the original owner? I ask Because we sold Newmar from 1994 til 2008, and hundreds of DSDP's. NONE--NONE came from the factory with 2 wall tstats. They came with the standard(your year) 5 button Dometic wall CCC Tstat. You then had the rear Zone 2 with the remote bedroom temp Thermister. Now, believe it or not, over those early years I saw a few Newmar's with just 1 Roof AC (DSDP Diesel and Gas model). Usually sold to dealers in the NE and NW. So, is it possible your model came with 1 AC and somebody added an extra and used a wall tstat? OR, there was a problem with the original set up and the Tech that was trying to fix installed that 2nd Bedroom wall tstat? My point being, you should have the communication wiring in place for easy change out to new Penguins and new 10 button CCC wall tstat. I will bet you also have the Bedroom Rear remote Thermister someplace in the Bedroom on the wall. Doug