I don't think anyone is saying they are innocent of all charges but the scary thing is the charge of drinking without a liquor license and of having illegal (by UAE law anything derived from opium eg. anything with codeine is illegal) drugs in their system, makes most western passengers on flights through the UAE criminals.
If the reports of their behaviour are correct then they should have the book thrown at them for that, but as far as the drinking without a license and having drugs in their system, well they sound like a bit of a crock.