The ENT has told you the truth. If she/he didn't put you on some medication for the acid reflux is surprising. Every one of the symptoms you describe can be a part of the GERD. It's treatable. You might want to see a Gastro MD for it. They do a Endoscopy to see what kind/how much damage is being done to your esophagus and they are up to date on all the new meds for GERD. Not to scare you, but GERD, left untreated, CAN eventually turn into cancer of the esophagus. It usually takes years to happen, but stop the GERD and the chance is less.
Can such problem really cause a offensive smell? I can't believe.
I am having acidity problem for last 8 years and now it is very much controlled. I am feeling nausea now and unable to eat properly.
The smell is not continuous. It can be felt directly from my nose and feeling the bad taste in the throat. The mouthwash (non alcoholic) can't hide the foul odour.
Also, my voice has been changed very much since last two weeks. There voice comes vibrating and i can feel the obstacles while speaking.