What an awful experience for both of you. The only good thing is that your mum is able to laugh.
As for the medical situation don’t forget that you have a fundamental right to ask for a second opinion even if you have to go private for it, this will not normally be refused. My mother did so, at the request of his pathologist brother, when my father was in hospital for the final time. He had been tilted head down to keep blood flowing to the brain, which had resulted in a recommendation to amputate his now gangrenous legs.