The main “complexity” with multi-signature is the descriptor file.
In order to “build” your multi-sig vault, you need the public keys for each wallet involved in that multi-sig.
Without the public keys, your wallet coordinator (like Sparrow) can not “access” your funds to build a spending transaction.
So if you do a 2/3 multi-signature, you can lose a seed, but you CAN NOT lose the descriptor!