The free action potion and LiP do not typically display its graphic in PVP, and more frequently when its a druid in animal form.
This also happens often, and its very easy to see it happening because hamstring and crippling poison come up “immune” charge, intercept, cheap shot, and kidney shot come up “immune”, but there is no graphic to show these effects are up, other than the immunity shown.
check your raid/battleground graphics settings, if projected textures is turned off you won’t see the effects! 
I havent really noticed an animation on LIPs before. What is it supposed to look like
looks like this
https://wow.zamimg.com/uploads/screenshots/small/868873.jpg
I thought that was the free action /blessing of freedom animation.
blessing of freedom looks like this, they effectively do the same thing though. https://wow.zamimg.com/uploads/screenshots/small/57804.jpg
I’ll check it tomorrow, that’s a good catch!
Ok, checked all my graphics settings.
All settings are apparently as maximum, and all the details are checked to on. No idea why I dont see any graphic for that.