My guess is that the original photo shows the "add on disease"...
First attempt= nail gun on sides; unsuccessful....
2nd attempt= dowels; unsuccessful because the nails are sticking out on the inside of the crack.
3rd attempt= telephone pole bolt. Successful in that the neck is still holding on, but not very aesthetically pleasing.
I won't say that any of it cannot be corrected or fixed, but it will take up a lot of bench time (= expensive...).
For every clean original neck Kay I see, probably 20 of them look like this, and the rest are in the middle somewhere. The street value is more like $600 three weeks after Christmas. It is important to remember that if this was done 25 years ago, this was a $150 bass so the work was considered reasonable for the cost involved....