After a numerous amount of close attempts, we decided to push for another 40 minutes past our raid time to keep the momentum going.. This is truly one of the most toughest encounters we've faced so far in WOTLK, as well as the most satisfying to defeat.
A job well done, guys. One Light in the Darkness and we're set (for most of us--we'll also be helping the other group get General/Freya/Mimiron round 2).