Your 2 A/C units operating at the same time would probably max out your 30-amp power feed. Most RV's that I work on that have 2 roof units also have a 50 amp power feed. IIRC, one 13,500 BTU roof air will draw almost 15 amps between the compressor and the fan. Interestingly, the new 15,000 BTU units draw less, only 13.5 amps.
Still, that leaves you with nothing to operate anything else in the trailer. An option might be to re-wire your A/S to 50 amp service so you can run both, but iy is fairly complicated and expensive. If you use the search option, I believe that there were some posts a while back from a member who did that, but I think it was in a MoHo.
Lew Farber...RVIA Certified Master Tech...ABYC Certified Master Marine Electrician
SOLAR TECH ENERGY SYSTEMS, INC.
AM SOLAR ...MAGNUM…VICTRON ENERGY...LITHIUM & LIFELINE BATTERIES…MARINE REFRIGERATION