Honestly I can see both sides. The fact that the mother can't go is completely understandable, given that no family members are allowed for anyone, but the lack of a personal assistant is messed up. I think 1 assistant per an athlete in needs sounds reasonable.
Although on the other hand that's one more person to keep track of that could be a Covid risk. Especially in the Paralympics games where many of the athletes are already immunocompromised, it's important that the games don't turn into some global super spreader event.
It seems like more and more people are dropping out both voluntarily and forcibly due to Covid diagnosis by the day. It will be a feat to just get to the closing ceremony at this point.