440 problems ,new motor

the result: the cam was siezed. we had to remove the block plug and hammer it out . The journals on the cam were clean but the cam bearings are scored up. Two of them started to push out as we took out the cam. One exhaust and one intake valve touched the piston on #2 and #8. I filled the ports with fluid and there was no leaks . no bent push rods.
still dont know if the cam siezed then the bolt broke or the bolt broke first .
thoughts ?