Neither the red tail or the hog is a pattern mutation, it's a locality. So none of the animals will ever be pure again no matter how many times you breed them back. Think of it like humans, if a Brazilian man and a Korean woman have a son, no matter how many generations of Korean (or Brazilian) babies they have the babies will still have some Korean (or Brazilian!) blood. We don't consider humans "hybrids" but with animals most people like to keep localities (bloodlines) pure. You might be able to re-home the hybrid babies but there's not a huge market for them so it might be difficult.
Hope this helps. Good luck!