If I remember and understand Tom's issues with the Blood Cult correctly, his objection was to the names, not the substance.
Change the names in the BC to be more medieval-fantasy and less Mesoamerica, and I'd say there'd be no problem with putting it on Dwilight.
If I remember correctly, this was not the case. It really was that he wanted european-inspired religions and cultures. At least, if it was only about the names, then I was never told, and that's not really something I was inflexible about.
