We are getting a second opinion and checking on the cost of having the engine rebuilt, if possible.
My son was driving the car when it happened. The radiator overflow hose had blown off and spewed white residue all over the inside of the car and there was no coolant when we got to him on the side of the highway. The oil level was full. He said he was using cruise control going about 75 and it went up a hill and he let it kick down. It kicked down, revved the engine then all the lights on the dash started flashing and it just shut down after that. He says there were no dash warning lights on, but I can't confirm that - I picture him cruising along at 75 not paying much attention to anything but the blaring radio, he's 17.
Thanks!