Or until it turns out that letting the Daimon religion gain sway is even worse then the blight. Might just be me but if anyone at all linked to Overlord was offering to remove the blight, I would be very suspicious of what they ask for in return.
Nothing is worse than getting beaten by Riombara.
And since Riombara was starting to annex Enweil's old lands, well... The means tend to justify the ends.
Fighting to prevent regions from getting blighted is one thing. Then getting backstabbed by your neighbor who then promptly seeks to annex your lost lands... Whole other game.
Guillaume, for one, was reluctantly willing to cooperate with Rio to defeat the daimons. Thanks to Hvrek, and the Riombarans who never stepped up to him until he appointed himself to a region, he couldn't care less about the daimons today. I'm getting a feeling that anti-Rio resent is probably pretty strong in Enweil today, but that's more of a hunch than anything.