cannot complete this mission period. the last two squad i see before the final spatial charge are one shotting any support that beams in, a single captain has zero chance of surviving the damage long enough to even kill one of the 3 in these squads let alone the whole squad.
Even if as a tac i use tac team and then use tac inititiave so i can bring in another set of security they down them too qucikly to kill the squad which resets if you don't kill them all. so again game progression halting due to a bug. and i'm unable to find a workaround this bug.