Tricky question about Atwood Water Heater

Those are strange symptoms...but the 3 strikes thing reminds me of a problem I had with my old '94's water heater. That turned out to be a bad spark igniter circuit. Once replaced, that particular issue was gone. Your heater though, sounds like you've got 2-3 things going on. So I'd recommend checking your main ground for the heater. Also check all the electrical connections under the lid, be sure they're clean. Both ends where necessary.

Note that the thermal disks and chemical fuse can all be shorted out to test them so make yourself a shorting wire.

Here's some pictures when I worked on mine: Water Heater Repairs