OK, i am trying to understand what you mean
First, get your chopper to land WITHOUT using a getin / load Waypoint-Combo.
You could do this using snYpir's excellent land_chopper scripts, of which different versions and flavors are available.
once the chopper has nearly landed (@(getpos myhelo select 2) <= 3)
have the group-leader run a script
[leader groupname] exec "checkready.sqs"
In this script, have each unit assigned to the chopper as cargo
{_x assignAsCargo choppername}foreach units group (_this select 0)
and then order them in
units group (_this select 0) ordergetin true; (should work - not sure. if it does not, try{_x ordergetin true} foreach units group (_this select 0).
Last, have a check if all units are in the chopper
(If you are NOT using a script, _this select 0 wont work. in that case instead assign a name to the group leader and use that name instead of _this select 0.)
siren going, will end this l8r