I also went to one of the best gastroenterologist I can find and he diagnosed me with SIBO but the treatment did help. I think that's because he also gave me stomach acid suppression drugs and no diet to follow (I was eating grains and everything). He gave me a pro-kinetic agent because my gut muscles where not working properly and so the food was staying in one place for longer durations. That might explain why I don't feel hungry in the evening.
Every doctor I have been to has given me stomach acid suppression drugs saying that the belching is due to acidity and heart burn. I have taken acid suppression drugs for almost 4 months before I read about how they aren't good for candida infected people.