Is it true that there is no absolute morality?

[Kernel Sohcahtoa]

I'm perfectly willing to stipulate that if God created people with a specific intent to behave a certain way, then that would be objective from our point of view.

What about from a more universal point of view? Would it still be objective, or would subjectivity become more apparent at that level?

Its not that God adds something but rather that God is that something. You should know from your study of ancient philosophy that God is described as 'the Good' a concept repeated in Aquinas's 4W, degrees of perfection

Is it possible that there could be multiple sources of that something?  Or put another way, is it possible that god is a source of that something but is not necessarily the only source?