Hi Dave Welcome to the Forums
most RV's have a GFCI outlet by the sink in the head- this often controls other power outlets ( on my pleasure way, the galley and outside outlets) check that this isn;t tripped- reset it.
this common fault has been responsible a number of times for owners thinking the worst has occurred
with electrical problems once the power supply is known to be good
( in this case power to your inverter), and all breakers are good, it is tracing power from outlets backwards to find the fault
I have old tech ( with propane!) and no inverter is required with my stuff