Engine noise and broken exhaust bolt (updated with pics)

My neighbor came over and took at look, he is a retired mechanic. In addition to the broken stud the rear stud is cracked. He has every tool they make and tried to see if the studs would move but no way, so its going into the shop today.

The shop runs two shifts and the light trucks are serviced in the late shift, the machinist is also not available on Mondays so I should know what's involved to get this fixed by tomorrow.