“So; this means a NON-human has to die to take away sin?”
if the Temple is up, it’s animal sacrifice. Since the Temple isn’t up, we have halacha as a substitute. And of course, the Days of Repentance including Yom Kippur.
Oral Law = instructions, judgements, and traditions before and after Sinai. Jews walk and talk, then write when they were about to enter Israel.
Think of an early judge.
So; the blood of oxen and lambs DOES take away sin; right?
The scapegoat would atone for all the sins in the Torah: https://www.scribd.com/doc/28390008/Maimondes-Hilchot-Teshuva-The-Rules-of-Repentance