Why do you think that they must eat bones?
Regarding her being toothless, it actually doesn't matter - cats gulp, they don't really chew. The teeth are more for ripping skin and pieces of meat off their prey. In a domestic environment, if the meat is soft or cut into small pieces, it's not a concern. My vet very stupidly informed me of it right after I paid $750 to have one of my cats' teeth cleaned/pulled...you bet I never paid for dental work for them again.