Still don't see anything wrong with a Cruiser taking an opportunity to pirate a trading vessel whilst pass through and spotting it randomly, camping somewhere in a cruiser doesn't make a lot of sense in RP, but this does (to me at least).
I believe (can't remember fully) that this guy was carrying ore of some description, so his cargo could have been worth 20-50 million, are you saying it doesn't make sense for a crew piloting a cruiser to take a few minutes to issue a demand for 10+ million and then kill him if he doesn't comply?