Will of Uul Netol Ring removing demon stitcher recovery.

I am playing Relic of the pact with ES from Foulborn Ghostwrithe and found out how to get my life down to 99% in one cast with Essence worm + The Will of Uul-Netol.

Demon Stitcher gives me recovery but it doesn't work when I equip the Uul-Netol ring. Don't see why it wouldn't.
Without ring and no reservation nodes I reserve 84% in one cast, but with it I reserve 99% or 98.82%.

Even when waiting for life to get to full before casting my ES only barely moves from Demon stitcher with the uul-netol ring on.

Without even waiting for life to recharge (Eternal Youth) I can facetank walk through lab traps without the ring on. A single cast brings my Es up by half regardless of my current HP at time of cast. So its not the amount of life left over to sacrifice. There is something wrong with this ring that is basically cutting Demon Stitcher's recover by 99%.
Is the life sacrificing after the cast and not during? It seems to be during when I have 84% reservation, because I recover insane ES when at almost no HP upon casting, and the same amount when I am at full hp when casting, but with this ring on even at full hp I recover peanuts.

I know ur busy ;(
Thanks for Reading I guess.

Bump ;(