We have 240 volt service to our Church with two 120 volt leads/legs and a neutral lead. A transformer on the pole failed during a lightning storm dropping one 120 volt lead. Electronic equipment in the Church failed. Was the electronic equipment failure due to the lost 120 volt lead or a possible voltage surge? We do have surge protection on the incoming feed before our main breaker.
There is a limit on how much energy can be dissipated or diverted by even a service entrance surge protector. A lightning strike that was able to damage the pole transformer probably destroyed your surge protector at the same time.
It was the surge that caused your electronics to fail, not the loss of one leg.
Good luck trying to get the "insurance" that may have enticed you to add service surge protection in the first place to cover your losses in full.