Tony and Elena decided to attack those Monsters from the left side while the others will attack those Monsters from other different sides.
When they have the advantage why should they not use that advantage against those Monsters?
It is a good thing that those monsters still did not realize that they got surrounded by Tony and everyone. Naturally that is Sam's plan.
Because of Sam they did not have to go that much close to those Monsters and can already figure out the location of those Monsters.
The moment they get a signal from Sam, Wasting no time they begin to attack those Monsters. Even without finding out the location of those Monsters they begin to attack
Naturally, they are following Sam's direction. They did not know but because of their sudden attack those Monsters really did not get the time to do anything.