Galactic Conquest Sector 5 "Guarded Assault" feat boss fight

In the Sector 5 boss battle I used Vader lead, Hoda, Thrawn, Malak and BSF, thinking that if I kept Vader alive then won I would get the "complete the battle, losing no attackers" feat (as Vader is the only attacker). However, both times I have done my strategy I have been unable to get that feat. I noticed it the first time, and the recording provided is the second. I got this by repeatedly MMing with Vader and alternating force crush and culling blow so as to get an infinite loop (TM reductions caused by force crush were enough, I guess)
https://youtu.be/epK47ORwgQ8