I did it g11 bsf, g10 hk, g8 cander, g9 juhani, g7 carth. Very few omegas and no zetas
A few things I learned in the 3 hours of that stage.
Wave 1. fear the leader right away. Don't break the fear. Pick 1 toon and focus him, you can use juhani to Stun the one that you broke fear on most likely the leader will need it. After fear ends on the group aoe shock with revan and follow up with bsf. That should clear the way.
Wave 2 is about resetting cooldowns while not taking a bunch of damage. Just pee pew them.
Wave 3. Do not use bsf are debuffs to start. Fear a marauder. Use juhani to Stun the other one. And burn it down. You need to kill those 2 before you spread debuffs everywhere as it will make them stronger.
Wave 4. Crap shoot. You could try removing all but 1 robot, I just did fear on main guy like wave 1. And would only damage the adds after they lost a turn.
My Ally code is 118-951-974
Hope that helps, it helped a guild mate start reaching wave 4 at least