If you are looking at covering the full 2 mi area, then some sort of mesh is going to be required. Simply put, you are not going to obtain 1mi distance without LOS conditions.
If you use the mesh functions of the SX, then yes that would work.
Digi does not support the processor so I can't say for sure which port for you to use. But if you can use the USB port as a COM port, then that would work. Providing you can Source the current that the SX module requires.