Same here using quick match and I can't join conquest or domination. I keep getting that "lost connection to session" message. --- "I am Reptar hear me ROAR!!!!!" The Joker: "I may be crazy enough to take on Batman, but the IRS? No thank you!"
Use the search server and look for a match with a few open slots. I had no problem getting in. Quick match is horrible, your going to get a connection issue every time. --- The Official Thunder Of The Killer Instinct Board