I find that Fabreeze doesn't work that well to get rid of smelly jeans. I mean it helps for like a day or two, but I'd rather hang them outside for a day.
Placing dryer sheets on your jeans and folding them helps pretty well too and rubbing them with the sheets.
Maybe someone can try placing your jeans inside on of those scented trash bags for a day or so and see if that works??
when its that bad, freezer overnight. and if they still stink after that, introduce or re introduce them to some water