If Claire McCaskill cannot win re-election in Missouri, then John Bel Edwards cannot win re-election in Louisiana, as Louisiana is substantially more Republican than Missouri is, without much of anything to distinguish between the states that could result in a switch in placement.
You're missing one little thing here...
John Bel Edwards has consistently had great approval ratings, while Claire McCaskill had underwater approvals.
You could make the exact same argument that you just made and swap LA-GOV with WV-SEN '18.