UPDATE
I had my gun looked over by a second gunsmith, who came recommended by a regional high end firearm shop. He ultimately gave me a clean bill of health on the gun with two “watch and sees”: one a hairline crack just behind the grip checkering, and the other the top barrel rib, which will eventually need to be reattached, as the muzzle end is slightly loose. Put my first few shells through it today. Pretty pleased with the news.