In order to resume successfully MP has to be able to understand/interpret/handle the sequence of HDMI device disconnect/connect messages delivered by Windows. My understanding is that the source of the triggers for these messages is the GPU driver. That is why I'm pointing the finger in that direction.If this was a simple Windows driver issue, it should not be possible to call any other entry in the start menu.
If this is a Driver Problem our only hope is that the Option "Wait x on Resume" is coming back in MP (or get fixed).