You are drawing on assumption, just because Satan was present does not mean they were angels gathering in Job 1. You do not realize you are denying the power of God when you say angels (ie. cherubim) can mate with humans. Even if they had the capacity they would not be allowed as Job shows us. Even the demons must operate within the boundaries set by God.
MY GOD REIGNS! View attachment 187490
lol, thats why I ask about their chronology first you see if the events in Job are prior to Moses(and they are) then in fact Moses afterwards wrote Genesis 6:4 and gave the additional information about the sons of God. Looking at it the other way the sons of God are in a meeting presenting themselves to God and then returning to earth...