Cecil's maze room was full of traps and the machine sound was indeed from the security system.It wasn't for the animals though,but for the other creatures he had brought down there.Plus there was more than just the machine system...inside of the maze also lay some of his old type machines he used to experiment on.As Rachelle and Andy had ran through the maze,these leftover robots had been roaming the maze no longer as sensible as they once were.They were now almost in a zombified state and needed energy to move somehow.They began to feed on the leftover organic matter from other dead creatures and had now set their sights upon the newest meat.They were now closer to both meals as they turned corners  to see them in their sights.