While playing the new Jingle Hell mode I noticed that my weapons wouldn't get the PaP while Mule's Kick was equipped, where before there was a good 50% chance it would trigger.
At first I though it was a bug in the new mode, but after testing it on both Astra Malorum and AotD, I can confirm that the augment simply does not trigger.
I have played one game of Exit 115 to showcase it, out of 6 PaP not a single time it triggered on any of the held weapons.
If you choose not to believe me, I urge you to try for yourself.