Tough Prisons

[Daniel Hall at IceTV]

This is true, it won't be known until it airs, however the episodes listed on Amazon Prime don't match up with the episodes of Inside the World's Toughest Prisons.

Both series are also currently listed separately on IMDB (and also on TheTVDB):

Inside the World's Toughest Prisons - https://www.imdb.com/title/tt6322264/
Behind Bars: The World's Toughest Prisons - https://www.imdb.com/title/tt15576176/