So like a 2 of 3, multisig, whereby the lender has 2 keys and you have one? Yes and No. Multisig is not the safe option it is thought to be. To recreate a multisig wallet you need the XPUB of all 3 keys, if one of the parties looses their keys and doesn't have the XPUB backed up and the original wallet is lost, there is no way to recreate this wallet and the funds are lost for ever. This is explained here:

I also don't see the point of this. Having only one of the three keys still leaves you powerless without the permission of whoever holds the others. Am I missing something?

I think perhaps a more secure way of lending would be with a 1 of 2 multisig walletb(borrower and lender each holding a key) with each party signing a commitment transaction for the term of the loan. The borrower is then timelocked from the bitcoin until the end of the loan term, but the lender can spend the bitcoin at any time. Then, the borrower has some guarantees that if the lender goes belly up during the loan period, then can retrieve their bitcoin after the timelock is up. But the lender has guarantees of the collateral value during the life of the loan. This is similar to how the lightning network HTLCs work. Just a thought. Not sure how that'd work in the legal world though. Usually a company that goes belly up sells off their assets, of which the loans still need to be paid back. But still probably better than traditional multisig. Time locks are great for inheritance though!