I did some calculations to figure out how long someone may have been in there for.
Its seems like it could range anywhere from 100 years to 1000 years, with most people probably taking about 300 years.
Though - these numbers all depend on whether the watchdog has correct answers.
Suicide after the green text simulator seems probable.
Here are my calculations, I did my best to label everything but it might still be a bit confusing at first.