I have a sneaky feeling that the docs at Brooks AFB were instrumental in getting the FAA to drop the Falant test. There are other tests that supposedly quantify the color deficiency, but you would probably have to visit a specialist to get access. Despite your fears that the new demonstrated proficiency is a way for the examinres to fail you - I would take the time to find one that you trust and get the letter of demonstrated proficiency if required. That way, it is over and done with.
By the way - according to USAF studies - at least 10% of those that pass the plates will still show signs of color deficiencies with more involved tests. And, given the % of males with color deficiencies, I am sure there are examiners who themselves have color deficiencies. With that being the case, I doubt they would be looking to fail people.