There are some basic things on your end you would need to make sure of before wasting other's time .
A good vehicle battery and a battery maintainer connected to it, all wiring and connectors to the transfer case motor and module has been inspected for water damage ,green death, and rodent damage , You actually have a circuit wiring diagram for reference and all basic power and grounds at both the module and transfer case were tested with load and were found to be good.
(If it has an external transfer case motor, it was removed and checked that the mechanical part of transfer case that the shift motor rotates, can be can actually be rotated through it's normal range of motion, and that the transfer case fluid was checked , replaced, and not found not to indicate any internal failure.
The update subscription and Quick Support App version of Team Viewer is current on your Maxi Sys Pro or Elite