Our DPS'ers are putting out between 2300 and 2700 depending on the attempt
Everybody is in full 72 level gear.
That doesn't quite add up. :/ You should be doing more DPS on that fight if you're all full 72's. Your collective dps should be above the 12k mark for the fight and that's possible even when there's people still partly in 69 gear. Might be time for your DPS to check their gear optimizations, builds and rotations.