So really, you didn't come to a conclusion, you are asking for consideration of the point "is there such a thing as Objective Ethics".
A conclusion can be a question, what I concluded incidentally was a question.

[The Ten Commandments] About as objective as you can get.
Yet is killing just? And it says: "You shall not covet your neighbor's house. You shall not covet your neighbor's wife, or his man-slave or maid-slave, his ox or donkey, or anything that belongs to your neighbor." So slavery is ethical?

It's [morality is] subjective, not objective.
But wouldn't that justify murder?"