Which Empyreal Lord(s) would you think someone would have the most success trying to pitch to a particular usually non-Good race? Assuming off the bat this evangelizing mystery cultist has the Charisma and the character levels to get them to actually listen and consider it.
Immonhiel, CG empyreal lord of herbs, medicine and toads would be one option for appealing to boggards, in my opinion.
Jalaijatali, CG empyreal lord of natural music, rapids and waterfalls apparently already has worshipers who are Good-aligned lizardfolk.
Olheon, LG goddess of deservedness, nobility and rulership might appeal to proud kobold chiefs, though you'd probably need to alter your art of her to make her look more draconic for them to take her seriously.
Any other ideas?
Ragathiel, as the son of a demigoddess of the Plane of Fire (and himself having grown up there), would probably have some pull with Ifrits.