3Teams-1Flag CTF

[VeniVidiVici]

Good evening,  

I would like to build a CTF for 3 player and now the problem is that only the West players and resists the flag can be lift and the west nd the resistant flag can't be lift. If the flag is put on west, only the east as well as the resistance canbe taken the flag. And if the flag is on resistant only the east and the west can be taken this flag.  
 
With this problem, I said to me, it must be a Civilian flag, but if I put a civilian flag, no team can lift the flag more.  
Do you kno? Which flag comes to receive into the init. line?  
 
Thanks