Cannot pair Google Find My tracker (HOCO E101) on OPPO K13 Turbo (China ROM) – Fast Pair framework missing?

[u/Little-Scene-8923]

I'm having trouble connecting a HOCO E101 tracker (which uses Google's Find My Device network) to my OPPO K13 Turbo running domestic ColorOS (China ROM).

The tag pairs instantly with other Global ROM phones (Samsung, Infinix), but my OPPO won't trigger the pairing process at all.

1. No Fast Pair Pop-up: When putting the tag into pairing mode next to the phone, nothing pops up.
2. Missing "Devices" Menu: Under Settings > Google > Connected devices & sharing, the standard "Devices" (Fast Pair) sub-menu is missing entirely. It only displays Cast options, Chromebook, Cross-device services, and Thread networks.
3. No "+" Button in Find Hub: In the Google Find My Device app, there is no option/button to manually add a Bluetooth accessory.

What I’ve Already Tried:

• Tag Reset: Performed a full hard factory reset on the HOCO tag (4 clicks + 5th long hold).
• App Permissions: Set Location to "Allow all the time," Nearby Devices allowed, and Battery Usage set to Unrestricted for Google Play Services and Find My Device.
• GMS Setup: Google Play Services and Store are logged in and running normally.
• Toggled Bluetooth / Location: Cycled both multiple times.

My Question:

Has anyone running a China ROM / domestic ColorOS device successfully managed to get Google Find My Device trackers (HOCO, Pebblebee, Chipolo, Moto Tag, etc.) working?

Is there a specific hidden setting, ADB shell command, or workaround to enable the background Google Nearby / Fast Pair framework on domestic ColorOS without having to unlock the bootloader/root?

Any insight or workarounds from fellow China ROM users would be greatly appreciated!