I'd be really interested to find out what the results of your strict diet are. I'm going to the ENT on Wed as I think that it might be my tonsils that are to blame, as my tongue doesn't ever usually smell.
If not that, then I'm going to go on a huge detox/colon cleanse/liver cleanse/general sort myself out and see whether I have any allergies etc.
I'll be very interested to find out whether you see any improvement. Not that I'd wish this on anybody, it's quite nice to know that there are other people out there who know exactly what you're talking about.
Where do you get a tongue brush from? I'm UK based and I've not ever seen them over here.