The entire point of the Black Chalice "Heresy" was that in a sense, it was a legitimate interpretation of Siamorphe's dogma.
My view on the Church of Siamorphe, that unlike most other gods, Siamorphe as a title, is passed down through her descendants, much like how a King or Noble passes their title to their heirs.
Morvyn was a legitimate heir to the title of Siamorphe, and by virtue of this, could access the divinity in the title of Siamorphe, and thus, bestow clerical powers onto his followers.
He was trapped in hell by the original Siamorphe, but with the Silence, the devils felt the contract by which they confined Morvyn could technically be breached if he inherited the title, and thus, they concocted a scheme to free him by letting him become the true Siamorphe, thus, making him a god on the Prime, bypassing the Silence, and having a god who owed them a solid and also could spread their influence- a deity who could guide their followers directly was no doubt a trump card.
He was defeated, the scheme foiled, and Hell is moving onto other dastardly schemes.
I got zero interest in continuing this plotline.
No from me.