Advice needed. A journal cap came off!

If an engine lost a main cap, there are going to be other issues. FIrst, what ense was missed? Second, the cap was hit on the mating surface (well the corner) and that may have bent the cap, and definately has displaced material and raised an area of the mating surface. If it was in my shop, the engine would be totally stripped, the line bore would be re-done, and the cap more than likely reused if doesnt show any bending during the inspection. I would not be bolting it, or another cap, back on. To me it's not worth the cost of the materials to "see". Call it overkill but we're not talking about a loose rocker shaft here...