Legend up and died while driving

I was driving down the road when all off a sudden it just shut off and wouldn't start back. Battery went dead. I figured the alternator right from the start , so I took it off and in the mean time I noticed that the ground wire that bolts to frame and battery had rusted and disconnected from the frame. I went ahead and put a new ground wire on but not sure if I used same hole . Had battery tested it was junk , had alternator tested it reads good . my buddy loaned me his jumper from snap onn and it keeps saying check connection. Me and a buddy checked for spark and it's not firing , I don't know it's driving me plum crazy please help