Almost every one of the fingerprint sensors in laptops are not supported by Linux due to proprietary protocols. Never managed to get stuff used by Dell or HP with Linux.
But the Grow R503 can be used over uart, what can be connected to usb with some minor additional parts.
Yes, as an alternative to klipper -this really is your end goal - use the firmware by mriscoc, it is really nice and robust.
Gives you more options and the results are better than the stock fw.