Well hell, if they smell that bad then find a roadkill carcus and shove them up any exposed orifice for a week, after that they should smell BETTER than previous

OK, now to make a serious response, kinda related to my previous jest.
If I recall correctly, on the molecular level of sweat, what makes it really stink is called "thiols", which is the same stuff in decomposing meat/flesh, skunk spreay, and human crap. Ironically, when water is introduced to this "chemical" it sort of activates it, causing it to multiply and hence making the stench worse.
Back in the country, we'd wash our dogs in a mixture of arm-and-hammer baking soda, drug store hydrogen peroxide, and a little dish soap when they got the bad end of a skunk and it worked like a charm. The chemical reaction of the baking soda and peroxide nutralized the thiols and the dish soap helped to wash the stuff out of the dogs hair.
Give that a shot.