: At least on Xbox it's been stable and haven't run into any technical issues,
: except for one lock that forced a restart of the mission which I think
: might have been in CE too, Rockslider might know—the marines had turned
: hostile to me (I'm guessing they were getting taken out by explosions and
: blaming me) and so when I got to the final rockslide area, once I cleared
: out the dropships Echo 419 did not trigger.

I followed your plan twice to see what happened. Echo 419 turned up as usual and it had a boarding prompt for me.

The first time, I let an enemy Marine board first. There was no prompt for me any more, and his AR fired bullets my way despite pointing a very different way. The Pelican just hovered. Maybe if I'd waited long enough to be forgiven, the prompt would've reappeared? The second time, I boarded before the one remaining enemy Marine, and got flown off alone.

Are you sure all the covies had been killed? I'm just wondering if you had one lurking in the rockslide, in which case the Pelican wouldn't have triggered.