I am a DM for my local D&D game and I always run my games with waring factions that can be manipulated to do things
My Players were facing down a Warlord who was leading a demonic army, my party was moving with a force of Island guard from a battle when they came across a group of scavengers who managed to hold off the horde in a village, the army force was hostile to the scavengers as they had stolen gear off their dead friends (as scavengers in a apocalypse warzone would do) however both sides had the singular goal of stopping the horde, as they had no other real option, being that they were on a island with a fast moving horde, stopping it was their only chance for a real escape or getting reinforcement, so they had to work togther, once they stopped the Horde they noticed the scavengers had retreated and stolen a boat before the battle had fully ended, along with all the gear they stole to spite being offered metals and honor for their service, as they were in the end enemies of the guard, so they made a escape while the Island guard cleaned up the remaining forces, once the threat is gone, it will not be long before the “allies” would turn on each other
same deal applies to this situation
If you Have the choice of Dying to Horrifying alien Nightmare bugs or Working with the people you view as oppressive dictators, you would always choose to side with your enemy, atleast until the Guaranteed death is dealt with, and then either Turn on or Run from them before the end, unless they have mercy and let you leave
but on this game more then likely some dumbass will ignore command, see you, think “they not marine, marine good, they bad, kill not marine” and start shooting at you regardless
My Take summarized:
to RP right look at it from your characters perspective, you are being assaulted by nightmare Bugs who use your friends to birth more of them, your alone and as far as you know no one is coming to help, so when people show up, friend or Foe, Your Odds are better with the people who will take you prisoner then the Aliens who want to use you as a Unwilling parent, and if you work with them getting away will be easier since your not their biggest priority