Is your mouse functioning outside of this? I mean is the mouse usable without the customization options of the RGB function? I am going to assume this is the case as Linux should be able to detect it as a mouse regardless.
It seems to have been updated in November but still has issues with certain devices, of which I am not seeing yours listed. I am wondering if this update may have messed with it? I am not finding any other complaints. It might be worth contacting the dev team.
You can get some help here: https://help.openrgb.org/