Firstly, you can update to v1.46 from the official site at
www.flashpoint1985.com. It's much better than 1.3. To get a version higher than than you need to buy Resistance (v1.75) or GOTY which is well worth the $10 - $15 it costs these days. If you can find a copy.
That alone might solve the problem. However, you shouldn't do it like this anyway. Never use player waypoints to make things happen - they are too unreliable. Players in Veteran mode can't see them so they may miss one, which screws up the whole mission.
You already have a trigger activated by the player, which is fine. Write this in the trigger
On activation: [resyLoon] join player
where resyLoon is the name of your resistance soldier. That should do the trick. Syntax not guaranteed.