The drycamping CGs have restricted genny times so having 2 gennys to run the AC is quite the expense for little return plus a place has to found for the second genny.
Seven long seasons, over 120,000 miles, lots of dry camping, no regrets just having the 1 genny. What we do have is a respectable battery bank & a large inverter. Nobody likes to listen to a genny, even if it is a Honda or Yamaha, so the inverter is great for charging camera batterys, phone batterys, some TV viewing & the small coffee maker & do it in silence.
For air, open the windows, the overhead hatches & turn the fantastic fan on.