Don't think that Charles will abdicate either, not least because he has waited so long.
I don't think he would
want to abdicate but it wouldn't surprise me if there's some exaggerated scandal (maybe something with the Church of England, since Charles isn't too crazy about being Defender of THE Faith, or some meddling in politics) that makes it untenable for him to stay on the throne.
Also the idea of him going with a different name kind of funny. He's been know as Charles for 73 years, they'll still refer to him as "King Charles" even if he goes as George VII