1.) How do I recover the multisig wallet in the event that I lose access to the computer where the wallet is stored? I.e. if the computer was wiped and I didn't backup the wallet, would the wallet, tx history, utxo set be derived deterministically from my 2 hardware devices if I were to setup a new multisig wallet on a fresh install of Electrum?
As long as nothing happens to your hardware wallets (or both mnemonic phrases to be more precise), you will be able to recreate the wallet in Electrum. Transaction history and UXTO will be fetched from the node. Why don't you give it a try? Create a new wallet file under a different name to see how it works.
2.) If I lost my hardware devices but know the seeds and restore them on different devices, would they be valid as signers?
Yes, but you might need to recreate the wallet if you use, for example, Ledger instead of ColdCard.