This is under the Class B shelf of Cincy's airspace. Cincy will typically not clear IFR traffic through, much less VFR traffic. In fact, I've heard one of the FBOs at the field tell pilots that they might as well cancel and go VFR over the top of the airspace, descending on the other side to come back in under the shelf. Saves 20+ miles.
We don't know the facts, but I certainly hope that this accident was not due to overflight traffic being compressed under the shelf and circumnavigating the Class B. We'll have to wait and see, but I hope the NTSB checks to see if one or both requested Class B clearance.