1. Reach the room with AT LEAST 6 minutes to spare (7 would be preferable).
2. Defender Titan, Sunbreaker and ArcLock seem to me to be the best team.
3. Our main strat was to get rid of Blights ASAP, then go ham on the Boss. Once the second wave of blights appeared, the ArcLock and Sunbreaker went ham on the adds and Blights with their supers. Then go back to wailing on the boss with swords.
4. Use Defender Bubble as and when required with the Armour of Light.
Our strategy with the boss was the suicidal brute force one, i.e., keep wailing on him till he kills you or you kill him. We were able to save a few revives by running for cover every now and then if we thought we it wouldn't be a waste of time.