Once again you are NOT reading; That partition has ALWAYS been hidden. ALWAYS. It has never magically appeared. The only thing that happens to it is that its label is erased, nothing more.
Have you tried to permanently hide it-- you can use Gpedit.mscAdministrative Templates> Windows Components > WindowsExplorer then look for the hide specific drives click enable then choose the drives
Now yes I have read everything ....
You keep trying to change something as an Administrator that is managed by SYSTEM.
I suggest since you are having hibernation problems-- to follow my link --
the one about removing the hibernation file- then defragmenting- then re-creating the hibernation file- it is possible the one there already is corrupted
PLEASE read before replying....