Yep this can happen when making the die cut. It also could be damage from installation if the die cuts on press. Most likely a mistake in preparation of the die cuts them self that was not seen or overlooked and make it's way threw quality control. You would find a number of these sheets. They would have been made in bulk. How may was made I would have known idea. Nice find and yes an genuine error in die cut. Good find.
This was not due to damage or improper manufacturing of the die cut mats. This was a big misregistration (shift) of the die cutting - the weird part in the middle of the stamps was supposed to be split between 2 panes.