Yeah its happened to me a couple of times too the loot is meant to be in the chests that unlock after you kill the boss but when they went down.. Nothing just a angry red locked chest with no loot
As for the first boss its reasonably easy just make sure to kill the dog things first witch will make it easier and keep them out of the red ring because while in the ring it will double their damage output also a thing to note is that they are immune to taunts so their agro will be random.
The second boss the Boarding Party is a pain and yes they are very powerful but the best order to go for (this is if your Republic) is Warrior Inquisitor Agent Bounty-Hunter
and be quick the one who the most pain in the back side is the warrior who keeps jumping around and uses knock bat witch can interrupt your party and cause havoc
but in the last patch they tweaked them a little so that you can CC them so that will make it even easier (I've not played it yet after patch )
Just keep at it and be as fast as you can as when each member falls the remaining ones get stronger one alternative in beating the fight is get each of them to 10% health then finish them all of in quick succession.
The third and final boss is a cinch just keep at him until he jumps and spawns turrets then kill the turrets then back on him just repeat it until dead