If everything has a purpose then evil doesn't exist

[R-Farmer]

If you remove god from objective standards, you lose the ability to make claims like "gods righteousness". 

yep, if you take the God out of Righteousness you only have morality.

There's nothing right about it, not really, unless metaethical objectivity is true. 

Indeed. God's righteousness in a moral frame work is in fact not right at all. Just think about that for a moment. why would we consider it right if the system of right and wrong has departed from God's original standard? The whole Purpose of morality is to create a standard of right and wrong that allows for the sins we want to retain. sins that God is opposed to. So if God says ABC is wrong, and we want to retain ABC, then would we not have to vilify God inorder to be justified in departing his Righteousness?

Outside of that, god's righteousness is merely gods godness.  Or gods opinions on stuff.  Or gods rules for being in his club.

  100% correct. But if you keep going with that line of thought and mix in a little Might Makes right. God's 'opinions' on stuff become the standard on which all are judged.

That you're looking for a way to make not just apparent evil but actual evil "perfect righteousness" is..to put it mildly...disturbing.  Maybe you should look into holding that amoral or immoral position genuinely?  It would be less work, less bullshit, and amount to the same metaethical outcome.

That's my point..
To what standard should or could anyone hold God to account? First, we do not have the "might" to make what we think is right anything more than a regional/generational preference. That would be like you walking up and knocking on the door of 1600 Pennsylvania AVE to serve a warrant that you your self drew up to arrest the president for violating some arbitrary rule that you personally live by.

None of which seems to be an issue of externality.  You explicitly mention that these savants have no formal training so..whatever theyre up to would appear to be coming from within.  Thus, they may paint well, or they may play well - but this would not be a successful vision quest by your own stated metrics.

Not with in. The documentary I saw on this says their conscious self is set aside and this 'outside force' which they do not have control of, plays the music, or paints a photo realistic painting, or does whatever magical thing they do. They are often times just passengers or observers in their own bodies.