If you can't place them in the editor you could try
..... place a west soldier and name it easyfind(or whatever you like), save your mission, open the mission.sqm in notepad.
Ctrl + F and find the name you gave the soldier.
Where you see something about class name="soldierWB" or something similar, replace the soldierWB with whatever class from the list above.
Save the file and then re-open it in the editor.
Preview the mission and there he is.