Let me plug OSH to Liberty, MO into Skyvector and see. Just so you know, this will be my first time helping with PnP, so I'm really excited and eager to help, but I might be a bit rough around the edges. Anyway, let me plug it into Skyvector and see what the verdict is. Will they be able to fit in one kennel? If so, I can put them in the back seat of the C172 and then bring a pax with me in the front seat and split the cost. Anyway. Once I get a rough estimate of the flight, I'll get a better idea.
As for the commercial flight, I work for Delta Airlines. I fly for free (which is why I'm in Phoenix right now). I'm planning on flying out to LA and seeing one of my buddies I met while I was in the Army. Working for Delta, I get two free checked bags. I normally just take a small backpack as a carry on. So I could take the kenneled bunnies as checked baggage. Either way, I'm definitely willing and able to help!! I'll reply again with what I can do as far as a private pilot.