Invisibilty potion not working for model and neither is partvisibility.

MEG Demo R3.1.8 || MM 5.4.0 devbuild Build #b9a2a8a1 || Papermc-100

Meg does not appear to apply the potion effects to the model. I have tried partvisibility as well in an attempt to bypass the issue, both failed. No console error, just doesn't do it. Here is the script:

mobflee:
  Cooldown: 10
  Conditions:
  - stance fleeing false
  - variableEquals{var=caster.tamed;value="yes"} true
  Skills:
  - setstance{stance=fleeing} @Self
  - potion{t=invisibility;duration=9999;l=5;p=true} @Self
  - partvisibility{m=momo;p=body;v=false;em=false} @self
  - effect:particles{particle=explosion_normal;amount=30;hS=0.4;vS=1} @Self

the stance and particles work as intended, but the potion does not. Furthermore if I remove the model and try invisibility potion it works just fine.