Just an update in case anyone else runs into this issue - several owners in the Oliver Trailer Owners group on Facebook came to my quick aid and the fridge is working well!! After looking to see that the propane was indeed working by turning on the stove and letting it run (I learned from Craig Short that if the flame is blue there is still plenty of LP in the tank, but if it runs yellow it is getting low - helpful tip!), I turned the fridge off for a few minutes. When I turned it back on, the propane caught and the fridge was quickly back in business.
This may be obvious to more experienced owners, but I'll share here for other newbies like myself: the fridge outlet does not work on the inverter, so the AC only works when you're plugged into shore power. I thought, incorrectly, that if I turned the inverter on I could run the fridge on AC power. Learned something new, complete with the diagram from the manual (also sent by Craig Short)
that shows the fridge is not on an inverted outlet.