What is known--the engine quit running suddenly. The shop that had serviced
the car said the car would crank, but the cam would not turn as observed through the oil fill hole in the cam cover. The shop that bought the car and did the repairs and is selling the car said the timing chain broke and the extent of the damage was limited to four bent valves, chain, guides and sprocket. What is unknown is the damage to pistons if any, or the general condition of the car, except I saw all the records. The car was meticulously maintained according to the books.
What to do...

Steve