There are many variables that could answer as to why the neighbors didn't take as much a hit as this house did.
here are just a few:
The other houses had a better bonded water main that also connected to other services via it.
The secondary drops were severed to the point that the neutrals at the pole were apart thus the one coming into this house only made contact with the primary.
As far as losing a neutral on a service only causing higher voltage on only one leg is a myth, remember the see-saw effect of a lost neutral, as loads on the higher voltage leg burn out the balance can shift the higher voltage to the other leg so damage can occur on both legs conning into the house, I've seen it happen.
I have also seen the lamp filaments get hot enough to melt right through the glass on the lamp from just a lost neutral so it is still possible that thats what happen, like was said, its the first conductor to pull free in a tree fall event since it is the supporting conductor, so it is common for this to happen.
If the primary came into contact with the drop to this house there would have been arcing everywhere, but it would not make sense that it would flow through appliances that had no other path to earth or return to the MGN since if it only contacted the neutral which is in most cases bare it would have brought the neutral and grounding up to the same potential with the MBJ in the panel, the only things that would not follow this is anything connected to phone lines, cable which could provide another path back to the MGN, the furnace hot water heater could also provide a path through the water and gas lines but this would not explain the lamps blowing out??
But it could have been a combo of both happening or a timing that the primary made contact to the neutral while the hots were still connected to the transformer thus giving a return through all the appliances in use just before the hots were severed.
If primary voltage did enter the house you should see signs of it like arc marks in the panels, cable/phone drop showing signs of over heating or burn marks at the demarks and such.
Things happen so fast in events like this that can make it hard to pin point exactly what happened and why but if you think about current paths that would have to have taken place sometimes it can jump right out at you, just look at which appliances were damaged and then look at what common current paths they share that makes sense to the damage you see, lamps would have to had the over voltage to happen between the hot and neutral, if the hots were severed then how did this happen, my first thought is the hots had to have still been connected but the neutral severed, this explains the over voltage that first was just a lost neutral that could have see-sawed from one leg to the other, or the primary came into contact with the severed neutral just for a brief moment which is all it would take.
In the end you customer still has to catalog all that was damaged and submit it to their insurance, carefully wording it as storm damage and not using the term electrical damage as most insurance wont cover damage from bad house wiring and they will try to wiggle out of it if you say anything that could be interpreted as damage from an electrical issue, let the insurance company go after the POCO as they have the money to do so.
