I'm sorry, but I don't. Can't you just use the Neutral Bomb Varient? Or are you going for something special?
Oh :/. Well I'm asking for a friend and he did go for neutral bomb though flag would be better. It's for a SWAT gametype, so I'd guess flag would be better there.
You could put both of the flag spawns at the middle. But there's no neutral flag. There's also no 4-way bomb or flag, either.