DuaLipaSuction do pursue the SEN. DD is very dyslexic, and got a poor UCAT score, but luckily she was the last year where Bristol did not require UCAT or BMAT and instead relied heavily on personal statement, which was her strength.
Once she got to interview, she thinks that medical schools were positively interested in people with SEN (I don't know the right terminology but it was all properly documented and submitted) but who would be able to keep up with the academics. There were only a handful to start with, though some have been diagnosed since.
He might phone them up, say he is being currently accessed, and that it impacted his GCSE grades and ask whether it would be possible to submit any report after the October deadline.
I would say that you need to be quite organised for Bristol as so much is done via placements etc, and the admin interface between the medical school and hospitals can be imperfect. A good training for future work in the NHS, but students need to be self starting. Oddly more academic courses like Imperial might be easier for the less organised.
We also looked at Ireland, though this was a few years back. At that point you needed 4 A levels as well as a language GCSE. You got extra points for Maths. It was possible to take the Irish equivalent of UCAT in January. I don't know what fees will be like now we are no longer in the EU. My guess is that fees are higher, but competition lower. Some, like RCSI, only take international students. US drug companies have invested a lot in medical research in Eire. If DD had needed to reapply she almost certainly would have had a go.
Another alternative, if you have the money, was Buckingham, the private University, which gave you a Leicester qualification. Too lazy to look it up, but you used to be able to apply in August post-results to start in January.