2007 Ford Edge dead?

2007 Edge 125,000 miles.  Check engine light came on. Temp gage showed normal.  Drove a couple more miles and the engine died at a stop sign. Would restart and idle (albeit a little roughly), but would die when put in drive. Drove another half mile and parked it to be towed to garage.  Guy is saying that the water pump let go, and that we may have blown the engine up. I had the hood up when we parked it to be towed, and did not notice any smells, losing liquid, or feel excessive heat.  Guy is saying we need to spend up to $2000 for water pump / timing belt/chain, before he will have any idea if head gasket blown or engine is totally shot.  Do I believe him or have it towed for a 2nd opinion?