Actually that is incorrect. The extension will indeed work with the original or the 2016 version of MR Jack.
What the extension does is add 5 characters that can be added to the game. It also adds a dynamic setup instead of the static setup of the original and the 2016 version.
Just because the characters are 10 years older does not mean it does not work with the extension.
Are the card backs the same? and are they of the same stock as in 2016 edition?