You've had a lot of terrible advice here from people who clearly have no understanding of the more severe aspects of autism.
My son is 10. His autism is severe and he has profound learning disabilities. There is no redirecting him, he solely follows his own agenda. I could put a punch bag in his room and he wouldn't take a blind bit of notice of it. In fact he has nothing in his room, save for his bed, because he throws everything out.
If I was to put up padding in his room, he would tear it down. I could tell him off or ask him not to, and it wouldn't make a blind bit of difference because his brain hasn't developed an understanding of this yet.
Luckily he doesn't bang on walls, but I have put him in a bedroom in our semi detached house which is not next to the neighbours. If I were to try and stop him banging, it would be me being thumped instead.
I wouldn't even consider living in a mid terraced house.
I once approached OT about sound proofing his room, and they said it was fairly pointless and isn't the magic solution everyone thinks it is. They wouldn't fund it and I certainly couldn't afford it.
That being said, if you were my neighbour, I would be more than happy if you were to come and speak to me to see if there's anything I can do. Don't go with the faux concern and offers of tea and cake though.
I'm always willing to answer most questions about my son's disabilities so people can understand him.
If I can do something to stop, or at least help, the issue, I will do it, because I want my neighbours to be happy in their own home. But there may be some times when it really is beyond my control, so I don't know what to suggest after that.
Maybe try the landlord or council, but they're unlikely to be of much help. They probably won't have any new solutions, and are keen not to be perceived as discriminating against a disabled person.