I have been fighting this same problem for weeks and none of the solutions I have read worked. I have found a solution that worked for me, however. Maybe this is buried in the forum somewhere and I missed it but here goes:
I am using the Microsoft Surface Dock. Turns out there is an update for the dock driver that, for me, fixed the sleep/hibernation issue. Go to https://www.microsoft.com/en-us/download/details.aspx?id=46703 and download the driver labeled "Surface_Dock_Updater_v2.23.139.0.msi". Install, restart and hopefully it will work for you too!