I would check your GFI recepticles in your Coach. My Crestron runs on one of the GFI circuits. Usually located by the sinks in bath or kitchen. If they have not tripped, then it could very well be one of your inverters is no supplying power to the circuit breaker panel which runs the GFI's and other loads. In some Conversions, the Inverter load can be by pass the inverter with a switch. I don't know if Country Coach had that option.
With a volt meter, test the out going 120 volt power at both of your inverters to verify power is on.