Any operation for rabbits is a risk.
Rabbits sometimes dont react well to anesthetic, but normally that is an after care problem- they are reluctant to eat after and insome cases require force feeding.
I agree with DanaNM, that vet sounds like they arent sure what they are talking about.
I cant remember the actual statistic,but I think its in the region of a third of female rabbits over the age of four develop ovarian cancers. (Feel free to correct that if I’ve gotten it wrong)
My point is, I would not put huge faith into a small animal vet that straight up declines a surgery, that is actually fairly routine.
I understand your dilemma at this stage- I had a serious falling out with an exotics vet, the only one in the country apparently. But after talking around, I found out there were other vets who were completely comfortable dealing with exotics, they simply did not advertise themselves as such.
Ring around clinics close to you and ask them their advice-some will actually recommend other clinics for procedures etc.