The first two times they go against Benjamin, many of them are killed in battle. I wonder if these men were not...men of God. Because the only fighting men who survive are a handful who took refuge in a certain rock!
I have been thinking about how to answer this. I would say offhand indeed some were not men of God obviously given the context of how this lil war came about obviously some were blatantly rapists. However I also thought to myself, not all the men that perished perhaps even on both sides were sons of worthlessness or were not godly. In wars in the Bible, even the righteous die in the wars. It's notable this section of Judges is at the end of the whole book of Judges and of course segways into the Davidic period. Right in the next books many both righteous and wicked fall in battles and wars.
Saul the son of Kish mentioned in the OP and of course would be the descendant of one of the survivors of this (perhaps Kish or one of his fathers listed in 1 Samuel 9:1) was one of the survivors of this battle and who knows maybe Saul's mother, grandmother, etc could be one of the dancers of Shiloh. Another little interesting connection is in 2 Samuel 21:12 David takes the bones of Saul to be re-buried in the tomb of his fathers and it is revealed the men of Jabeshgilead (the town destroyed and the virgin women taken in Judges 21) had stolen his bones back from the Philistines that had slain and displayed him and his sons and men as trophies in Bethshan.
Of course back to the context of war Saul was an evil king and died in the battle of mount Gilboa, but then so did his son Jonathan whom was a righteous man and mighty warrior all around and David's childhood best friend whom David laments at the beginning of 2 Samuel. Even for the case that maybe one side were wicked and the other righteous is flawed, because later in David you got both the wicked and righteous being slain all over, Abner Son of Ner and Uriah the Hittite were righteous, but they were slain just the same as Joab and Absalom were slain.
Just because some people die in war or elsewise tragically does not mean they are wicked, and of course it also doesn't mean they were righteous either. A key scripture from the Gospels that comes to my mind on this overall topic of morality and war and such is this:
Luke 13:1-5
1 There were present at that season some that told him of the Galilaeans, whose blood Pilate had mingled with their sacrifices.
[SUP]2 [/SUP]And Jesus answering said unto them, Suppose ye that these Galilaeans were sinners above all the Galilaeans, because they suffered such things?
[SUP]3 [/SUP]I tell you, Nay: but, except ye repent, ye shall all likewise perish.
[SUP]4 [/SUP]Or those eighteen, upon whom the tower in Siloam fell, and slew them, think ye that they were sinners above all men that dwelt in Jerusalem?
[SUP]5 [/SUP]I tell you, Nay: but, except ye repent, ye shall all likewise perish.
As for the point on the Rock of Rimmon and seeking refuge in the Rock of Jesus, yes that is a good point too and I had picked up on that. Of course the familiar symbol of seeking refuge in the Rock pointing to Jesus symbolically is linked in quite a few places in the Old Testament as prophecies towards the Messiah. Probably most famously, or at least in one of my favorites, in Psalm 18.
And yes, my first inclination is to say "you don't know me very well." but instead I'll say....Thank you. 
