Urine Guard Rabbit

Really bad mats in rabbits fur. Can I shave her?
Pretty much, the previous owner didn’t take care of her and she’s left with these horrendous, urine soaked mats around her rear and legs. I’ve tried washing/brushing/cutting them out (carefully, of course) but to no avail. She’s a lop with lots of skin flaps so it’s hard to get everything. I’m thinking the only option left is shaving her with a guard so we can start over and prevent this before it happens again. What do you think?
have you tried bathing them with warm water? I would cut the worst ones out gently with scissors and then using pet shampoo try to wash the rest out. Clearly you are having trouble getting them out and it will be distressing for the rabbit so your last option would be to shave them out, I would take her to the vet who can advise you and maybe do it for you as well as checking her over and giving you advice for the future.