When I use the tears Jon comes out but he doesn't summon the balors and the demons and I start hitting him with the swords and it says he near death but he doesn't die?
Have you tried talking to him. By chance are you invisible? There needs to be some sort of dialogue before the battle can really begin and before he dies.
Yes, something is wrong. He should come out an iniate dialogue with you. At the end of that he will summon 2 pit fiends and 2 daemons while you can only sit there. Then the fight begins, =)