Did this mission solo a couple times (good mission, btw) and then the 3rd time did it with 2 other fleetmates and a remarkable thing happened...when we were first let out of the cage to enter the arena, the force fields on either side were down, allowing us to access the other weapons cache and get a rare (blue) Batlthe instead of using the common ones down the hall.
What triggers that? Did it again afterwards, again solo, and couldn't figure out how to get the force fields down, nor even seem to get the option. Was it because it was a team? Or just dumb luck?
None of us in the team episode did anything to trigger the fields to drop...
Anyone know how to drop them every time?

Im guessing a bug. You can get the rare equipment after freeing the prisoners anyways.

ah, did not know that, I've never gone back down the hallway after freeing the prisoners, I go back to the fight.

I've already done this mission with all 5 of my characters and NOW I learn about the blue weapons.

Out of 10 characters, only 1 received a Rare Lirpa. Everyone else received a Uncommon melee weapon. So its not a certain 'Blue', its mostly 'Green' with a chance for a 'Blue'... (At least you have mission 'replay' if you want to try your luck again....)

I've done this a few times now that I learned you can access the weapons after you free the prisoners.
All but once I got a blue melee weapon, the one time it was green. But I always seem to get a different type of weapon, not a Batlth every time. Maybe if you already have a blue weapon of a certain type, you can't get it again. I'm gonna try banking or selling the weapon when I lvl again and redo the mission to try and get another Batlth.
I'll let ya know how it turns out.
Of course, Once ya get the shard of Kahless, which scales as you level, doing Coliseum just for the melee weapon is kinda pointless.