The secret things belong unto the LORD our God: but those things which are revealed belong unto us and to our children for ever, that we may do all the words of this law.
Deut 29:29.
Not a problem at all. While these individuals remain mysterious, the Lord has chosen not to reveal anything more than what is in the Bible. This list is just that—it serves to wet your appetite and read it. But there is much more in the Bible that is “mysterious.” How about the “sons of god” mentioned in Genesis? Who were they and did they really mate with human women?
And who were those three guys that walked to meet Abraham in Genesis chapter 18? And they ate lamb, something that if it is good enough for God, it is good enough for me.
We are not to know everything it seems, and we do not.