If you are talking about the specimen quest, it counts individually. Just play cautious and if your teammates want to get squashed to bits, let them. Also recommend the first battleground to go flawless on out of the three. The other two are possible, but require a more coordinated team, particularly in the final boss sections of each. In the first one, I just hung out at the back right hand side by a tree plinking things with Choir of one, from there, the only thing that can really threaten you once the Fallen are cleared out is the Barrier Hobgoblins that will try and snipe you.

You only have to go flawless. Your teammates don't matter for it.

[quote]Attempting to run a flawless quest in a team setting creates a bit of a conundrum. Cautious play rather than normal aggressive play style may offend teammates if they are not aware of the situation. For that reason I think flawless runs as a goal should only be on a solo play basis. Players should strive to do the best they can for their team and not worry about dying.[/quote] Load in solo and don't worry about teammates.

Or you could make a fireteam and let your teammates know that you are doing the flawless battlegrounds and that you going to play very careful. Try that one chief, instead of crying.