Glad Major is OK. Watch the wound. It may swell over night and he may need some antibiotics. Good idea to get a taller fence. Go with 6' if you can.
I understand not wanting to have problems with the new neighbors. I am on the fence as to whether or not you should call AC about this. They had the dog on an insufficient lead, and they were not able to control their dog. They no the dog is not friendly. But they need a wake-up call. They need to carry a break stick and know how to use it.
Maybe they should muzzle their dog in public, use no more than a six foot leash, and carry insurance on the dog.
And should your dog need to go to the vet tomorrow (swells in the night, you find more injury), they need to pay for that as well.
I would say the same thing if the dog next door was a Doberman, Rottweiler, German Shepherd or Yorkie-Poo. Doesn't matter. A dangerous dog's owner needs a wake-up call.
But that is definitely your call to make, whether or not to try to remain on good terms by not doing anything, or calling about the problem. I am truly not sure which I would do.
ETA: I am glad that they came to ask about your dog.
Of course they may have been around this block before.
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