I completed the ritual as promised.
I posted my experience in the OP Struck With Satanic Lightning: A Ritual From Satan Himself to break the Chains of Religious And Spiritual Tyranny and To Initiate Dark Ascent - #4 by Mulberry
This came across for me as an assumption of godforms-style ritual.
The purpose of this is not to ‘become the god’, but to shroud yourself in the energy of this form, so that your systems resonate with it, and unwanted out-of-resonance energies can be shaken loose as it were, to be discarded.
No pact was offered or made at any point. Not that I expected or asked for one. 
That whole line of thought in this thread is a red herring. Whoever said that didn’t red the ritual and didn’t think before speaking.
The most useful take away was that Satolas used this ritual to make clear contact. The chant is where the power lies; I’m reading the lightning part as extra. The little bit of Latin at the end is surprisingly meaningful.