That is odd that the small light comes on with electric - that is the gas side lockout lamp. When I was having a problem with my gas side, the electric side would still work fine.
Couple of options - do you have a multimeter? If so, there are two tests you can do --
1. Remove all power to the trailer (ac/battery) - pop off the switch panel and check the switching using continuity mode on the meter. That should tell you if they are working properly. Kind of doubt that is the problem because I dont think even a faulty switch should lock it out - just make it not work - but I could be wrong.
2. If you look at my signature, there is a link to a library of manuals. Under Atwood, there is the service manual. It goes into how to run a basic diagnostic on the board using a multimeter.
If you end up believing it is the circuit board - you can find them online all day long for $125 and install it yourself. I am not aware of any reason Atwood would not warrant a new board if you installed it yourself.
Let us know what you find.