Anyone have any idea why I'm getting these errors when trying to use the sandboxer?

12:49:05.91 [INFO] Initializing scheduler...
12:49:05.93 [INFO] Trying sandboxer socket path /run/pants/b85ec67a0d83283d/sandboxer.sock
12:49:05.93 [WARN] Failed to create dir for sandboxer socket at /run/pants/b85ec67a0d83283d/sandboxer.sock
12:49:05.93 [INFO] Trying sandboxer socket path /var/run/pants/b85ec67a0d83283d/sandboxer.sock
12:49:05.93 [WARN] Failed to create dir for sandboxer socket at /var/run/pants/b85ec67a0d83283d/sandboxer.sock
12:49:05.93 [INFO] Trying sandboxer socket path /var/folders/v7/qb819xs91_55px65swlk4nqr0000gp/T/run/pants/b85ec67a0d83283d/sandboxer.sock
12:49:05.93 [INFO] Using sandboxer socket path /var/folders/v7/qb819xs91_55px65swlk4nqr0000gp/T/run/pants/b85ec67a0d83283d/sandboxer.sock

It seems to work eventually so is it just trying different paths?

Yep! https://github.com/pantsbuild/pants/blob/3da4be212bf1bae50112b221f15c5c5b80fd6a52/src/rust/process_execution/sandboxer/src/lib.rs#L398 https://github.com/pantsbuild/pants/pull/22625 as a possible spot to offer an opinion