Plot hole: If Quinn has the timer that could be used multiple times without trouble, why couldn't he take back Remmy and Wade then come back and save the world in peril?
The Other Slide Of Darkness - S3-E21
Plot hole: Quinn once again meets the alt-Quinn that he met in the pilot episode. Alt-Quinn tells our Quinn that he remembers solving the final part of the equation on his chalkboard. The problem is, there are many...possibly an infinite number of Quinn doubles in the multiverse. How could alt-Quinn have possibly known he was talking to our Quinn?
Chosen answer: Quinn's brother was going to be a recurring character, so "introduced" in this case referred to the actor becoming a semi-regular.
Jean G