He would be the VP candidate. You're not going to find someone who agrees with you about every single policy. It's unlikely that his support or non-support for school vouchers would ever make any difference in the world. Maybe if he's president in four or eight years it might, but I'd be thrilled to have the problem that President Josh Shapiro (D) likes school vouchers.
Same goes with Kelly and organized labor, and I also doubt that any union votes are going to be affected if Kamala were to choose him as VP.
Finally, I think it's long been disproven that VP candidates can deliver for their home geographic areas. MAYBE an extremely popular governor could help a ticket in-state (the Big Gretch argument), but that's an if because people vote the top of the ticket. And there's no evidence that they help out of state. If Josh Shapiro is making the difference for Dems in PA, we're probably losing.