If you give one of the private keys of a multisig address to another person, can he/she regenerate your other private keys because your wallet is deterministic?
You have to clarify your question, as it depends on the wallet structure, and what private key you're giving.
Think of the wallet structure as a family -- you have grandparents, parents, kids, grand-kids, etc. If you hand someone over a private key belonging to a kid, then they can easily generate all private keys belonging to their kids. If you give someone a privat3e key belonging to a parent, they can't get the grandparents private keys, but they can get any of the kids or grand-kids private keys.
Hope that makes sense.