Lance's lobotomy was a Real Method: Transorbital lobotomy, Invented with a Icepick, grapefruit, a rubber mallet and a cadaver as a cheap method that could be done with out painkillers due to asylums' often low budgets.
And of course, his having gone through one at the end, complete with the finished Apocalyptic Log.
Lance finding photos of the Grave Encounters team being experimented on in the final five minutes of the movie.
In fact, Lance's entire descent into insanity after Sasha's disappearance.
The sheer mindbreaking reality warping the Hospital is capable of. The second the team decided to stay the night at the place, they were doomed. Their food rots like its been there for weeks instead of hours, the sun never rises, and the doors just loop back into the building. Time means nothing there.
The implications of the Hospitals true nature. Its implied by some occult books Lance finds in the operating room that the head doctor may have created the place through experimentations with black magic.