If there are players outside of the final objective POI there needs to be an extended timer for extraction.
I, along with 5 others, just lost our characters (I lost a genuine god roll character, too) because a team of 3 just did a power plant speed run without telling anyone. We were at Sluice gate looting and healing when it was called and we had to run 500m, just for it to leave when we were about 15 seconds away from it. All they did was mock us in the chat and spewing hate slurs in prox chat.
For reference, the powerplant didn't have staggered objectives, it was the codes and it wasn't updating for us. All it did was tell us when they got to the power plant and when they called extraction.