Our level 7 group is playing CoS, and last session we had a party member (who is a wereraven gloomstalker) kidnapped by baba Lysaga, who then proceeded to implant a bunch of red worms into the ranger's body; the worms clinged onto her heart and since then she is feeling ill and cannot polymorph anymore.

I want some ideas on how to tackle the issue next session, but I can see all my ideas being denied by the DM, as he usually makes our moves fail unless they are original and smart.

Other players are dragonborn druid (me), dwarf paladin, tiefling bard, tiefling barbarian, half elf warlock, aasimar sorcerer. All lvl 7.

What I thought so far:

1) Attempting a surgery, together with the paladin; we are both good in medicine and could probably go through the saving throws;
2) Acting as a good druid and looking for herbs that are known to kill helminths, like neem, triphala or clover; knowing our GM, said herbs would probably be nonexistent in Barovia, or fail;
3) Casting stone skin on the victim in an attempt to make the parasites' teeth break (the RAW says that the person's flesh would become hard as stone, but one would debate whether internal tissues count as "flesh" or only skin and muscles);
4) Use healing magic that cure diseases, but it's not written anywhere whether parasites count as disease or not.

Any other ideas would be welcome!