Bosco,
I have a 788 in 22-250 also. I had the trigger mounting pin break off. Back when these rifles were still being made it was pretty common for these to break while the roll pin was being driven out to remove the trigger. You have to put pressure toward the reciever then drive out the pin. The mounting pins were just brazed in place.
Your gunsmith may have broken it when removing the trigger. It could have already been broken but I doubt it because it worked before. Any competent Machinist or Gunsmith can repair this easily by tapping a bolt in it's place and drilling the hole in the proper location. Better than new.
