and have found that gutloading once a month with natural sources of preformed A like- cooked chicken (no seasonings or BBQ sauce LOL),
fish oil, scrambled eggs (these are fantastic for a lot of reasons-amino acids) and even small pieces of cheese and dollops of yogurt seem to work well.
These things periodically, along with regular sources of betacarotene (as we are unsure how well chameleons convert this- and it doesn't become toxic at higher levels) have worked for me for years and are a more natural means of supplying needs....
Just my thoughts though..