Andrew Jenks’ documentary Billion Dollar Babies: The True Story of the Cabbage Patch Kids will obviously appeal to fans and collectors of the famous toy brand, but it should also reel in viewers who are obsessed with streamable studies on snowballing catastrophes (Tiger King, Fyre, Pepsi, Where’s My Jet?, Trainwreck: Woodstock ’99).  This nichey flick doesn’t boil over with ridiculous, jaw-dropping climaxes, although it is a shock and a hoot to watch ‘80s video footage of…