If it has a provision for forwarding all assets (with the necessary internal state detailed) to another address/DAO, then you can basically perform a migration to a fixed version.

There is no such provision. You can transfer the "balance" of a contract to another, but not any of it's internal state. This is left up to the programmer and AFAICT, they didn't implement this feature in the DAO contract(s).

Or a malicious one. The move has to be voluntary.