'Stop drill' the ends of the crack. Once stopped, I can't see how it can effect anything else. And if you bore for a sleeve, the remaining wall integrity is not anything you can count on anyway. Take a bore that has a walled thinned to .150" or less due to core shift, bore for a .093" sleeve, and you have <.060" wall remaining. Not much strength left there anyway. So the crack issue goes away IMHO, as long as you stop it form extending into the upper and lower ends of the bore. The orientation of the crack is good in that regard, since it leaves the vertical strength of the other parts of the bore intact.
