I am trying to do a calibration of my MVP with dji assistant 2, but have a problem connecting to the drone. specifically there is an error with the digital signiture for the device driver
libusb-win32 devices
     vision(interface 3)

Has anyone encountered this problem?  I think I could temporarly disable signiture validation on my Windows 10 PC. but I think it owuld be better to have a valid digital signature so as not to compromise security.

It is a known problem DJI has not addressed.  DJI's Assistant-2 is not "Blessed" by Microsoft.  

During install of Assistant-2, Windows rejects Un-Signed DJI drivers.  You have to turn off Secure Boot in your PC's BIOS, and run install program as Admin to get Assistant-2 installed.
See this post and this post.