macOS stores FindMy cache data in an unencrypted format at the following path on macOS 10 (Catalina), macOS 11 (Big Sur), macOS 12 (Monterey), and macOS 13 (Ventura):

$HOME/Library/Caches/com.apple.findmy.fmipcore/Items.data

This unencrypted cache has been verified on official Mac hardware (Intel/ARM), and Docker-OSX, but the docker VM approach may run into icloud issues.

If you just need 3rd Party API access (not within iOS), AirPinpoint supports both AirTags and third-party MFI trackers with a REST API