Probably not a mob_grinding_utils problem
Experience rod(from ender io) shift right click on singularity tank -> XP tap -> Player got more experience before

mob_griding_utils version : 0.1.8.16
Ender IO version : 1.10.2-3.1.179

FTB Invasion modpack version : 1.0.4

Might be same issue or relate to this issue(#26), I made a separate issue just in case.

Hello,
This was fixed in the latest version 0.1.8.18 - I would suggest updating.
Thanks for reporting it :)
Cheers,
Me.