I think, if you are really a friend, you should confide in her and both should see a doctor. It isn't normal for a sneeze to smell, much less stink. Perhaps you both are sucking the same pussy, that's a dead give away.
This doesn't make any sense. Sneezing having a smell and stinking up the place? Go see a doctor if this story isn't bullshit. There could seriously be something medically wrong with the two of you.
Diabetes is said to cause stinky sneezes,but stinky sneezes are quite common in normal,healthy people as well.
My wife is in her early thirties,as healthy as can be and exercises regularly.She has the smelliest,stinkiest sneezes.(not that its a bad smell I find it attractive and have a fetish for it).It has been like this since we were dating at college,over ten years ago.
Every time she sneezes,there is that cinnamon,musky smell.
She has a wet sneeze emitting a lot of spray and her sneeze is more from the nose than the mouth.