I too have had trouble finnishing an 18 hole foursome , with all 4 people anyways.
If I see all of us "loading" at the same time for more than 20 seconds, I close my game browser and hit Play Now on home page browser and re-enter game. Other player may have to do the same to re-enter.
This works most of the time for me, sometimes -1 player.
At least some of us can finnish the round :)
It seems to happen when one player has a connectivity problem (or quits) at the "wrong" time to lock up the game.