No. It doesn't work like that unless you're bat shit crazy.

They sacrificed as population control. It controlled the population. It also slated its bloodlust. Also necessity, culling it by ritual genocide, the condemned, hostages, sacrifices. Because any god bestows fear and is perceived as powerful when it demands sacrifices. Pretty soon you have a population of warriors? They sacrifice to their god, they probably have other blood rituals, providing a perception of power through fear.

The real conspiracy is how many did the Spaniards kill. They tortured the demons out of them in their quest for the gold. Rewrote their entire language, destroyed their religion, assimilating parts of it. Yea they probably deserved it, they were savages.

If you think it's a deal with Satan, you're mistaken, power corrupts because it can. It corrupts the innocent when they are helpless because it is the predator. What does it gain, if it can it does.

Most have a moral block. But what happens when it is severed and corrupted. What happens when it gets a taste for evil?