Good news story,
An issue with IOS that is almost 3 years old now, will be fixed in the release IOS 11.3. which prevents MDM's from removing passcodes on supervised IOS devices, of which have been turned off and on after receiving the message, iPad Disable connect to iTunes.
The bug would only occur if the end user had turned the device off and on, after locking out the iPad, preventing usb connectivity.
So far 3 for 3 attempts with the IOS 11.3 beta have been successful.
Although I am not sure if this will function with direct LAN access to the MDM of if internet is also required, which in some proxied environments may prove to be more difficult... if it turns out that it does... the process might be capable of being completed from home, if your MDM is accessible publicly.
To network connect an iPad you need:
1x lightning to USB cable and charger
1x USB to ethernet adapter
1x Lightning USB 3 camera adapter
You connect the lightning to USB cable and charger to the camera adapter, and then the camera adapter to the iPad, and the ethernet to usb adapter to the camera adapter. Note: you may need to update the camera adapter first, but connecting the adapter to an unlocked device, and update it through software updates via settings.
Disappointingly this does not appear to work with internet sharing (system preferences > sharing) via a macbook and a wpa2 home configuration, or at least thats what I have found with my testing so far.
After Lodging 3 reports of the bug to Apple starting back in 2015, via https://bugreport.apple.com apple finally started to get in contact with me last month to attempt to rectify the issue, after a bit of back and forth... Making me very happy to share with you that all IOS 11.3 supervised devices will remedy this problem, which should save everyone with supervised devices a whole bunch of time.
11.3 is supposedly going to be very education targeted.
My next push on the bug report team, is to have profile control over accessibility settings and time settings.