On Wednesday she was in the uni-clinics. The doc there obv checked her quite extensively and then said, maybe the cramps aren't really cramps but kind of chippings of the meniscus that at certain movements or whatever link themself somewhere where they shouldn't be because they are "swimming" freely in the knee. He gave her a prescription that she "rides bike" on a hometrainer (which we don't have, that's why the prescription) without any resistance, that she improves a bit the mobility of the knee. But he already made her the next appointment in the week after Easter to see her again. Well, we still think (and he also said there is the possibility) she has to be surged again.
So a different medical opinion from others you've had previously then. But either way it seems that surgery is still the road they'll be going down. How is she supposed to do that if you don't have one? Unless your mum is expected to find a nearby gym where they are available. Have they prescribed anything else she can do which will help to improve her mobility?