Very cool to see how it seemed so easy for you. I have done this instance at about the same level as you (and completed it) but i had a lot more problems with a similar team (4 melee, 1 healer, all monks). The trash only gave me trouble if i pulled 2 packs. The bosses i had to try several times.

My guess is your paladins came fully epic out of MoP (possibly 530 ilevel or up)? I boosted all but my tank to 90, so they came with a only 483 ilevel set and then some quest and garrsion upgrades