Shaman 2nd Wind Shear Interrupt fails on Goliath in Spires of Ascension?

I’m not sure if this is a bug or not, and yes I am aware that this is inspiring week. I’ve already killed a few high keys due to wiping on goliath fails to interrupt on its 2nd cast of rebellious fist (yay for not having a backup). I am able to successfully interrupt anything else OK, and usually the first goliath cast. The 2nd one is where I spam my kick and it doesn’t seem to trigger.

Here’s a screenshot where I recorded myself and the goliath was away from the inspiring mob, I trigger my windshear interrupt , it goes on CD, but the NPC is still casting. I usually do not experience significant lag and this was a pug. I was not lagging in the instance prior to these happening.

We then wiped after we got hit from the Goliath.

Imgur

This is my macro which has mostly been successful with interrupting my focus target or main target if I don’t have a focus set:

#showtooltip
/cast [target=focus,exists] Wind Shear
/cast wind shear

I use Threatplates as my name plate addon and yes this was an interruptable cast.