Unfortunately, communication isn’t going to make a real difference for them if there’s holes in the way they execute on certain modes. Hate to break it to people, no amount of communication is going to make a team change overnight. Game sense, understanding roles and rotations, how to adjust against different types of teams - it all matters. Communication can’t fix it.

Also:

3 people on the run for the next

Yeah this isn’t going to work.

3 people out at 20 seconds to the next point, that makes zero sense - your anchor would be holding an off angle at the next cap, roles at this point don’t matter - other three players should be holding portions and map control to protect the anchor - anchor holds your spawn point closes to zone. Basically a “cone of vision” to prevent their spawn from rotating. From there your last guy, who plays cap would die on the rotation (or make it back, either or) and he’d be anchored in.

Then he and a support hold point.

The best piece of advice for him is to watch some professional teams - watch old clips from the previous titles (Standoff BO2) and see the setup of a team in action. Watch from a players perspective from Tribe on mobile, they follow the meta currently, watch how their teams are rotation, how each player fulfills their role. On more objective based game types like Domination and Hardpoint, focus on how they anchor, when they rotate, how many sit point - they make adjustments on the fly. A lot of game sense and experience is the only way to gain that kind of knowledge but it helps to see.

If they simple watch videos and focus on a team like Tribe and how they play then go into the Discord and find other teams to scrim, they could mimic those setups and eventually it’ll come to them in time.