What about Tesla Warranty?
According to the official Tesla Vehicle Limited Warranty document, the warranty of the vehicle as a whole is not voided when installing 3rd party accessories.
Only if there is an issue with a specific part of the vehicle (broken part or something not working as expected), proved to be caused directly or indirectly by the 3rd party accessory, this part has a limited warranty, and Tesla might charge for replacing it or diagnosing the car.
For now, Tesla is OK with 3rd party accessories and doesn't state anywhere that the vehicle warranty is voided entirely because the 3rd party accessory is installed.
We have clients who went to Tesla Service with the buttons, and they just removed the OBD Commander and placed it on the passenger seat without any issues or warranty limitations.
We always recommend removing the Commander from the car when going to Tesla service to avoid issues with the staff and/or wrong interpretations of the global Tesla policy.