When Alex, Trevor and Jennifer meet Lance, he has a very cloudy left eye (it was the eye that was entered into for the lobotomy). Later, when Alex and Jennifer meet Lance at the gate where they are supposedly able to get out, we see the cameras floating around Lance. Both his eyes are perfectly fine, scene cuts and when cameras again go back to Lance, his left eye is again cloudy.
When they are returned to the asylum we see their camera footage as the doors open, revealing they are back in the steam tunnels of the facility. However there is an edit to the security video from the elevator and it shows that nobody was currently filming with a camera.
When Alex enters the studio in attempt to interrogate the filmmakers behind the Grave Encounters movie, the date on the security camera shows the date is November 31st, 2011. The month of November actually has 30 days.