Trezor One with 1.5.2 firmware, no seed

I have an older Trezor One with 1.5.2 firmware. The seed has been lost. The Trezor was locked away in a safe for several years.

I’m able to view the contents of the device by plugging it into my PC and visiting the old wallet website, but it calls my holdings a “legacy wallet.” I am able to move transactions to a new wallet, but I cannot send transactions to any other address. I get “failed to compile output” when sending.

Any suggestions on how to proceed as safely as possible would be greatly appreciated.