You should keep your Wink hubs and use them as z-wave repeaters for the Hubitat. This forum post details how to do that:
If you position your Wink hubs such that the first WH is within range of the Hubitat and the WH in the garage is within range of the first Wink hub, I think a single Hubitat will control z-wave devices in your garage.
@ogiewon has already indicated that you need the Lutron Smartbridge Pro 2 to migrate your Caseta switches and Pico remotes.
