Tyler, I think you are spot on. That Ohio goofiness is an additional problem above and beyond the technical and other financial issues. I believe it will happen if Michigan wants to run it, which they ought to since it most likely brings more business to Detroit than the other way around.
Michigan has actually been working with Amtrak off and on to reroute one of the east coast trains via Toledo - Detroit. The problem still is the miserable state of the route between Toledo and Detroit. It will need some significant funds to make it reasonably usable to run a credible passenger service rather than a token unused one.
Also, I doubt that any through train from the east to Chicago rerouted via Toledo - Detroit will ever go to MCS. It will stop at Dearborn as he Detroit area stop. It will add just too much time to its already long running time from the east to Chicago to go through the gymnastics that it will take to get it to visit MCS.
Another issue I see, is where Toledo's train station is in relation to downtown. Downtown is a mile and a half from the station, and requires you to walk through a less-than-desirable part of the city. Especially when it comes down to what time trains arrive (between 12AM and 7AM), it makes it even worse. The station has gotten better considering it has become the Grayhound station as well, and downtown Toledo is revilitalizing, but I simply don't think people would take a train to Toledo from Detroit unless it was business, a one off (Let's try a train kind of crowd), or if they were connecting. I just can't imagine a lot of people wanting to visit Toledo unless they have family or there's something specific they want to see, as in Toledo isn't exactly a destination city. Uber and lyft aren't very big in Toledo, and there are no rental car companies anywhere near the train station.
Detroit isn't really a destination city as well, especially if you live in Toledo or NW Ohio - most people will drive up there instead of taking the train, and MCS is nowhere near downtown Detroit either - and the area around MCS is dangerous. I have been almost mugged taking photos of MCS. Not sure if this will change with all of the things going on, but there are still a lot of issues here.
This problem isn't as simple as funding a train, it's multi-tiered.
On the flip side, one of the biggest attractions in the Detroit area is one of my former employers, The Henry Ford Museum, which is right next to the Dearborn Amtrak Station. So it would be good in terms of maybe getting those who want to travel to the museum from Toledo. Maybe even sell packages where you get tickets and train tickets.
Edit: added content.