This is something everybody would love to see or read about, but unfortunately the prospect of Joffrey meeting Robb Stark in battle are 100% extinguished thanks to their fun and tragic deaths respectively. The original plan would have ended badly for Joff, but fatally for Robb. The Young Wolf would have seriously injured Joffrey, before Tyrion and Jaime Lannister swept along and killed Robb, a totally different method of death to the Red Wedding. It's not all bad news though, Joffrey would still have been hacked down in a different battle.