Squealing Belts?
I am assuming the sealing surface of the harmonic damper is not painted... I see you removed the belts and it still squealed but otherwise, you can pour water on a belt and if it goes away, it is the belt, if it remains, it is usually a bearing. Did you remove the alternator belt? If not, pour water on the belt and if it remains, I would say it is an alternator bearing.