Why no passphrase on a cold card and derived entropy for the other signers. Geographically distribute the one set of words also with coldcard functionality. No need for multiple devices. Never selling.
Discussion
If your seeds are derived from shared data, then they are at the mercy of that data and anyone who has it.
Each of your signers’ seeds must come from different, original entropy. Deriving seeds from shared entropy reintroduces the single-point-of-failure that multisig is intended to fix.