[Morning]

The simple answer is no. Unless you already have 8 or more friends waiting to play with you. In which case you can just tell them to connect directly to the server (assuming of course you have set up SourceMod, MetaMod:Source and L4DToolZ to remove the human limit)

If you want 8 random players to join, you need the 8 player lobby because games / servers dont appear in the matchmaking menu unless it's being played via a lobby and it has free slots.