My Grandpa as part of his gig running the training center hired the pilots in the early 60's. I think he was done with that by 66 though and doing things with the DC-9. I think the last non-line flying thing before he went to Saudi Arabia was to be TWA's guy with the investigation of the DC-9 mid-air with the Baron in Urbana, OH in 1967. I remember - and it's one of my earliest memories - taking Grandpa to Municipal for what was his last flight from that airport. Grandma drove him to drop him off because when he came home from that trip he'd land at MCI.It was awful on him, I had no idea how bad pneumonia got until I watched him deal with it. Good thing is now that they have figured out his immune deficiency and they are managing that with infusions and they are giving him allergy shots that actually work.
As for your grandpa it sounds like our families are distantly intertwined. My dad flew for the original Midway Airlines and they operated the TWA DC-9-10s that your grandfather flew. As for me, my first job in aviation was as a ramper for Executive Beechcraft at MKC. Hangar 1 there was TWA’s back in the day and we would get into the condemned part of the building where their flight operations offices were. One of my good friends dad was a pilot for TWA and was hired in that hangar in 1966.
Lots of history at that old airport.