Nothing looks damaged. a 3/8-16 hardware bolt goes into both stud locations in the head just fine. the studs which are 3/8-16 by 3/8-24 (I think) will not easley thread into the head, or a 3/8-16 hardware nut.
So a 3/8 coarse bolt goes in smoothly - but the coarse side of the studs you have will not? Nor will the coarse side of the studs accept a 3/8 coarse nut? I would be scrutinizing the studs not the head.
I would chase the threads in the head with a 3/18 16 tap and shop for some new studs.
