Hello and welcome,
Thanks for your query.
I understand your frustration, and shall try to put forward another possibility.
Halitosis: is bad odor or breath which is exhaled during breathing.
This bad odor can come from:
Let me not go into the details of other parts and stick to the nose, which is what you want to know.
The most common causes of this exhaling nose odor could be:
Diagnosis: Halimeter or gas chromatography
Please discuss the possibility of a foreign object in your nose that could be causing this or request you doctor to look into other possible cause.
I hope I have succeeded in answering your questions, you could write back to us anytime for further clarifications.