[Visual77]

I'm not sure I fully understand. Game modes can be set from lobbies or from root access. Other servers could be running a versus/coop only server, (by preventing mp_gamemode overriding in a plugin or server.cfg).

In general, a game server can support all of the game modes, that's why you probably can't predict what "game modes" a server has installed.

You could however make a query on the sv_gametypes+mp_gamemode value, still that doesn't guarantee anything in my opinion.