Did you ever find out what was causing the smell? I seem to be suffering for the identical issue.
I am now completely off all dairy. I can tell it's still in my system though. Nobody in my family has celiac but I am getting tested Friday. Thats what the Dr. was thinking too. For the overgrowth I've been taking Oregano Oil and colloidal silver with strong probiotics for 3 months now and haven't seen any improvement. He is also testing me for H. pylori because I mentioned it but he thinks I don't have it for sure. It's weird though I get the rotten egg odor almost within 10 minutes of eating those certain foods. Just like a door opening letting all the potent gases out. It's just so hard to think it's getting absorbed into my blood and letting this potent odor out so quick. But anything is possible. I always thought it was candida/Leaky Gut going into blood stream and sweating it out but after today it almost felt like I was blowing it out. Very frustrating!!
Are you off of all dairy? And anything with casein in it? Casein is the protein in milk and it can be just as bad a drinking milk.
The other thing I'm wondering is - is anyone in your family celiac, and do they have to stay away from wheat, rye, barley and oats? In some with celiac, they're cross-reactive to casein.
Typically with celiac, you can have fat malabsorption and that can cause a foul odor, although no quite like fecal material............but I'm wondering if there could be a connection in your case. It's a wild shot, but it might be worth a try to go gluten-free and make sure you're casein-free and see what happens.
Another thought might be to be checked for small intestinal bowel overgrowth (SIBO). Your symptoms don't completely fit, but?