I feel really sorry for the poor buyer - we all know the excitement of getting a machine - and this was his first .... at least you can help him a bit Retro.

Like others have said, I'd be chatting to Consumer affairs about the transport company  - they clearly stuffed it and can't walk away as they claim, that's there first response.  Put complaint and claim to transport co in writing reasonably to document you are trying to resolve with them in a calm professional respectful way and when they do nothing up the ante to CA.   I guess it's CA from the state it was dispatched from?  Get pictures for evidence and maybe hopefully the seller has some of it as dispatched.  I take it the seller was private?

For pins in Q I've not purchased whole machines from him but I have heard nothing but good things about Tony from the Pinballshed.