I had this happen wih a crew, but never a broadside. I immediatly learned how to deal with and take advantage of 'Rouge Broadsides' because I'm one of th very few people who are like gods when it comes to sailing. I think It might of been a glitch, but it seemed I was so godly that they ran away, which triggered 'Rouge Broadsides' I can't control.
P.S. It was right after the first Treasure Fleet on Saterday.