Executioners Cleave vs Tatzelwurms

[Tether Me Daddy]

I'm playing on GMGOW Difficulty(Blind), and I've noticed that most of the time (Not always, approximately 80-90% of times), If you perform executioners cleave on these buggers, It does not act properly.
As you know, when executioners cleave hits, it is supposed to lock both you and the enemy into a special animation, during which you are invincible.
What ends up happening is I still get locked into the animation, but the enemy does not.
It takes damage from the first 'cleave' attack, but before the follow-up 'kick' hits it just burrows.
But what is worse is that during the animation, the camera does not zoom in and I don't get the invincibility, only to be slaughtered by other mobs(you die in 3-4 hits from anything).
Remember when you first meet Sindri? Immediately after you get attacked by 4 of these wurms and like 8-10 ranged dudes. I died like 30 times during that section because of this 'feature'.
This has to be a bug, because occasionally I do get the animation properly.
Anyone else experienced this? And is this issue exclusive to GMGOW? If so, why?

[cheetah1546]

i will see if I can recreate it