Berzerk ran out of robots?

Tonight I caught something on camera that I didn't think I would ever see again! I exited a room and the following room had no robots in the maze, I ran like crazy for the bottom exit escaping before Evil Otto could take his revenge! Here's the clip of the empty robot room!

I would not say this is a glitch, if I had to guess this is done by a random number generator that dictates the number of robots that are in a room. This is a very cool and terrifying thing to see in person!