Absolutely NO ONE holds that quinoa is hametz.
The issue is whether it should be treated as kitniyos (i.e. similar to corn and rice) since it might be mistaken from a prohibited grain, since one can use it to bake bread. The alternative is to treat like potatoes or turnips, which can be made into a flour, but are permissable according to everyone. There are plenty of opinions on the matter, and there is clearly no consensus among rabbanim. While quinoa has been around for a long time, it has only become common in the United States recently, so there hasn’t been time to decide if it is a new type of corn, or a new type of potato. Anyone who says the Daas Torah has decided the matter should say “My Rav holds…. “.