If you want to verify whether your CD does more than create black dyes, you could make a test where you substitute b&w developer for the E6 FD. Add 2 ml/l rapid fixer (thiocyanate would be better if you have it) to the b&w developer. After this dev and a stop bath you can look at the slides in normal room light and should see a b&w negative image, use this to find working dev times. If you then continue and finish the E6 process, you should see some color image, albeit with off colors and possibly some color crossover (we're not using the correct FD after all). If you get this result, you at least know that your CD and your BLIX work.