I've had 100% success so far.
Skip all optional items in the missions except the last one. Do NOT fight the Rikti Warlord, it is quicker to end that mission by not fighting him.
In the last mission, use Mark and Recall if you have it and mark the lab entrance. Then go get the first one and have them fight alongside you and clear out the freaks as you approach the second one, then free them. Now take them both with you and get the third and when they are ready use Mark and Recall. After that move up the hallway to near the sewer tunnel door, spawn lores and other pets, use barrier and set the pets on kill mode.
Do NOT let Dreck approach the lab defenses, YOU and your pets are the ones that must take him down.