I know it's a holiday; however, I'm sure someone can give me some information.
Happy 4th, GH. I'm about to run out for the day like most folks, but I'm never too busy for an old friend...
If I had to bet, I'd bet that the wall wart was fuse or breaker protected well enough to isolate the main board. And the fact that your lights came on might be a good sign.
But it's always possible that enough juice snuck through to cause some damage. If it was a lightning strike, very weird things can happen that no fuse or circuit breaker can protect against. I've seen the potential static field be enough to blow things.
Many years ago I had a Ham radio rig in my room. There was a storm coming in, so I not only turned the radio off, but I disconnected the antenna an stuck the antenna connector plug inside of a glass drinking glass laying sideways. The antenna was grounded via a 6th grounding rod stuck into the ground, and the AC power was double-surge protected (besides the main 20amp circuit breaker).
Well, we suffered a lightning strike on the telephone/electric pole in my neighbor's back yard maybe about 100' from my room. (There may have been a branch of that strike on my antenna, but I can't say.) None of the electrical breakers were tripped, even though (maybe because?) the transformer on the pole exploded.
Yet strike blew out the final output transistors on my transmitter. This is usually cause by something coming in the antenna. Yet even with a grounded antenna and the coax disconnected and electrically isolated, there was enough of a field charge in the air to blow the finals.
In your situation I don't think there's any way of knowing for sure until you actually try it. Though I'm optimistic. I know that's not much of an answer, but it can go either way.
G.