Given that: 
- a party character (human/wereraven gloomstalker ranger) got kidnapped and had an experiment done on her, during which she had six red worms implanted in his body (the worms clung to her heart, making her sick and unable to change her shape to raven); 
- some comments suggested this is not from the CoS book, and the DM probably created this situation; 
- the party as a whole is willing to help our ally heal, and the DM is receptive to ideas if those are creative and have no obvious downsides or side effects;
- Other players are dragonborn druid (me), dwarf paladin, tiefling bard, tiefling barbarian, half elf warlock, aasimar sorcerer. All lvl 7.

What spells or actions would help fight these body parasites?

What the group 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 required;
 2. Acting as a good druid and looking for herbs that are known to
    kill helminths, like neem, triphala or clover; I don't know if those exist in Barovia, so this course of action could be ruled straight out; 
 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, what is not clear is whether internal tissues
    count as "flesh" or only skin and muscles);
 4. Use healing magic (like lesser restoration) that explicitly cure diseases and conditions, but it's not written anywhere whether parasites count as disease or not.

Would any of those ideas work, or is there a spell/course of action we did not anticipate?