Hey longtimeuser,
You mentioned an issue with Bluetooth between some of your Apple devices. Does Bluetooth work as expected outside of that, such as if you attempt to pair or use other Bluetooth devices with either your Mac, iPad, or iPhone? That will just verify that the Bluetooth functionality is working overall, rather than just in the sense of unlocking your Mac with your Apple Watch specifically. If Bluetooth is working correctly other than just with unlocking the Mac via the Apple Watch, it might be best to Get Support directly from Apple as there may be some deeper steps that they'll want to complete with you.
Take care.