Hi!
That's a terribly complicated condition for moving. Besides, all you need is a synchronized GET IN waypoint (for the infantry) and LOAD (for the helicopter) -> now the squad leader will order his men to enter the helicopter, the helicopter will land, and once they're loaded it'll continue in its waypoints.
The only problem is when you're the squad leader, or if you're in the group but alone - for the synch to work the leader has to order a subordinate to enter the helicopter, otherwise it will just hover and wait for all eternity (AI units can order themselves to enter a helicopter, but if you're alone you're out of luck). In this situation, doing the "land" thing that your instructions have given you will work better, except you do NOT NEED TO SYNCH ANYTHING in that case. But the condition is clearly overcomplicated. Instead, do this:
1) Name the group that is entering the helicopter by adding this in the group leader's init field:
group1 = group this;
Now group1 is the name of the group. Next, in the Condition field where you normally write that terribly complicated long list of !alives and so on, simply write this much easier command:
{vehicle _x == helicopter} count units group1 == {alive _x} count units group 1;
As you can see, the above command compares the amount of people inside the helicopter with the amount of people alive. Once the two match up (i.e., all living members of the group are in the helicopter), the condition is true and the chopper will take off.
Also, if this is just a quick extraction, you might want to use land "get in" instead of land "land"; then the helicopter will hover just above ground and wait for you to get inside before flying off. I don't think you need the dostop command either.
Hope that works.
And welcome back to OFPEC
Wolfrug out.