GM, Frens!
May the Good Lord bless each of you today, and always!
Shooter was standing 10 feet to the right of Charlie.
He had a weapon under his arm then concealed it right after the shot.
Guy in white hat was a spotter looking at a close-up video on his phone a third accomplice was live-casting of the laser targeting dot from the shooter's weapon.
When the shooter was on target, white hat guy gave an arm signal shooter could see in his peripheral vision then pulled the trigger.
This explains why Charlie lunged to his left upon impact.
third accomplice….the one live-casting the close-up of targeting dot…
was the drone.