I note the comparison between Harvey, who has severe autism, Kathy Lette's son Jules, who is at the other end of the spectrum. People who have high functioning autism like Jules can live independently and form romantic relationships so the idea of him going for a punt to scratch that itch needn't be controversial, even getting your mum to arrange it for you is weird.
Harvey isn't like that. He will need round the clock care for life and probably isn't aware of what sex is. Is it right to do this with him if he can't verbally agree? Would he even do the job properly?
This seems like a publicity stunt to me.