Yup dose with prep h and gently coax it in hold it several seconds. Doing that several times or at least a couole times a day is how i had my success with my Buffie.
Sounds like whatever the outcome she knows she is loved. I had a full size hen who had a much worse prolapse and who with the treatment plan your following and gently pushing the prolapse in and holding a few seconds several times a day she did recover. So keep hope and continue loving and...