IMHO, the poster is wrong.
"... the strippers, JFK and Stalin" is a list of three items of equal grammatical importance. This describes the first picture.
"... the strippers JFK and Stalin" or "... the strippers: JFK and Stalin" would create a parallel structure where "strippers" modifies both "JFK" and "Stalin". This describes the second picture.
"... the strippers, JFK, and Stalin" has a redundant comma. The 'here comes the next item' function of a comma is served by the 'here comes the final item' function of "and".
You don't write "I invited JFK, and Stalin." do you?
And by not writing Oxford commas for ten years I saved almost enough time to write this post.
