It's not like they do some sort of roll call at the gate at the 45 minute mark. Generally, you should be relatively safe in an oversale situation if you check-in early and have a seat assignment. But, yeah, 34 minutes is cutting it close and there doesn't appear to be any other same-day options if you miss the CDG flight.
Yes, there is no roll call at the gate. But, yes, GA's (and Ops) can all see who is connecting and who won't make it to the gate ontime. DL counts on misconnects to deal with overbooking, so this is neither sinister nor odd.
Unless OP has mission critical meetings on both sides of the Atlantic which make this routing the only one doable, it is folly, given that there are no other options out of CVG and we have no idea what the onward options to IST are.
OP has a chance to reroute because DL has booked him an illegal routing. Why not take it?