Open Neutral and failed transfer switch

we purchased a 201203 cyclone 3110 last Fall.This summer while at the beach, we came back to find our electric off and bedroom tv, central vac, and microwave fried. Before telling the campground what was wrong, anticipating and immediate cover up, we just told them our electric was flickering. They checked the pole, nothing was tripped. The used a tester on it and everything was still showing OK, then we told them what we found. No one else had problems, no storms, nothing. We found out after talking to a tech that it was the transfer switch. We also found out from a retired electrical engineer that an "open neutral" can occur and cause a power surge frying the 110 appliances. Now the dealer, is telling me first that the progressive dynamics switch can not get open neutral. so I contact PD and find out it can. Now the dealer tells me that if it was open neutral I would definitely have some burnt wires in the switch, witch we did not have. I just have a feeling I am being jerked around. We purchased a cheap surge protector that mounts on the pole for shore power to protect the switch, but we also bought a wired in surge protector for around $400 to wire in AFTER the switch to also protect our appliances if the switch fails again. The dealer says our swith just failed but did not cause damage to the appliances. it had to have been something else. Does anyone have any thoughts on this issue? I would appreciate info from someone other than the dealer.
Tammy