Yes, probably due to not all players initializing at same time.
Either, put <this moveInCargo heli;> in each unit's init
Or, in init.sqf:
sleep 1;
waitUntil{alive squadleadername};
if(group player == group squadleadername) then {player moveInCargo heli};
If you have AI enabled, you might have to do this:
sleep 1;
waitUntil{alive squadleadername};
if(isServer) then {
{if(!isPlayer _x) then {_x moveInCargo heli}} forEach units group squadleadername;
};
if(group player == group squadleadername) then {player moveInCargo heli};