Max 4 GRBL firmware BIN missing from NEJE server

I need the correct GRBL firmware BIN for my original NEJE Max 4 controller.
My controller currently shows

System v2.3.1, NEJE v2.3.1 and GRBL v0.0.0.

The updater reports:
Update task: grbl
Downloading bin file…
Downloading bin failed.
Update GRBL failed!

Chrome DevTools confirms the updater is requesting:

https://cdn.neje99.com/firmware/neje3/grbl/grbl_v2.3.1.bin

That URL returns 404 Not Found. The System and NEJE v2.3.1 BIN files download successfully, but the GRBL BIN does not, so the updater never reaches the flashing stage.

This is not a USB, driver or controller communication problem. The required GRBL file is missing from the NEJE CDN, and the machine is currently unusable because GRBL is showing v0.0.0.

Please provide grbl_v2.3.1.bin, or an earlier compatible GRBL BIN for the original Max 4, along with a supported offline flashing method.

Thank you

Shannon