St Pete 99 T/A

What up people, i need some help. I was driving about 80 on a bridge when I suddenly lost power and my SES light started flashing. There was no noise just a loss of power. I pulled over and noticed my car would bearly run and running VERY rough, no smoke from the exaust or any other discrepencies. I took it to the dealer and was told no compression on #7. I took a fiber optic scope and looked down through the spark plug hole and seen a nice round peace of metal with a gash about 2 cm deep. Anyone's 2 cents on whats going on would be great as well as recomendations!!