I've googled this and asked developers but can't find an answer. One of the endings for the Followers is that you can convince them to support NCR if you're siding with them, then after the final battle the NCR will let them stay in Freeside and help people. But according to The Vault it's currently bugged, though it hasn't been updated since the new patch came out. Does anybody know if this was fixed and how you persuade the Followers to support NCR?