Look yeah it's a pathetic act to run away after seeing someone murdered your friend, but the Goddesses are also kinda dumb for giving prophecy like that. Like literally the moment after he got the prophecy, he got murdered??? Yeah it's not Their fault that some human are evil but like the timing is just so bad. As others had said, even if he did tell everyone that the High Priest is evil, he would be killed and this whole arc won't happen. Like you would know best how dangerous he is. Also don't you know of the power of words and rumors? People could have said he was jealous of High Priest, etc etc.
It's just that yeah this FL didn't forgive her family but at the same time she did start to help them a lil bit. So how come this side character get preferential treatment? Just because he is a side character that didn't deserve your 'empathy'?