I'm not sure I fancy little ones chances if you werer to remove it completely but if you cant get littleun to feed from mum in that way then you could supplement its feeds with some goats milks or replacement kitten milk and take it out to feed it but pop it back with the others when done?
that is exactly what we have tried and he is still with us and is a tiny bit better, we are hoping he will make it, i also spoke to a vet and it was suggested to give the kit a tiny drop of honey about an hour before we try this, that gave him the boost of energy to suckle whereas before he had no energy....its just so lucky i have such a good bond with dora, first i held the kit in my hand and she gave him a good clean (i also did that after i gave him the honey so she could clean it away from his tiny little mouth and nose) she is 100% secure with me, she has fed the babies while i had her hutch open, she also allowed me to keep trying to put the kit under her belly several times.
so what we tried first was me laying dora on her back and exposing a teat (oddly i didnt expect her to let me as she hates her belly being touched)...the kit tried to suckle but i dont think he was getting any, so dora let me move her more onto her side and then he had a good suckle, he didnt get a round belly but you could clearly see the wrinkles in his tummy were less, this could all fail and we could still lose the kit but at least we can say we fought for his tiny life.....i just hope it works.