I played around a bit and It seems like this but is very easy to recreate.
I do not know much about mod making but I have noticed that the point bug only happen when one or more parts of uke touch the ground. It also appear to only give points to tori no matter the situation (even when tori doesn't hold the grinder and both uke and tori touch the ground).
Points only start counting when:
1) Uke's parts are touching the ground.
2) grinder is touching wall or the ground.

I don't know what to make of this but I hope this information helps in solving the bug.