And remember to make sure that the mission will still end correctly/work out ok even if the loon doesn't get to the waypoint. For example, if the AI unit is supposed to drive there he may crash into a tree and not make it.
If you want something to happen when the player reaches a certain spot, use a trigger and group it to the player unit so that you get the new options in the On Activation box. If order is important (for example a previous Objective must be completed first) then use variables to turn the trigger on an off
Activation box: group leader present
Condition: this and obj1