"I've been looking elsewhere and it says to rarely feed your sugar gliders honey, yogurt, and apples/applesauce but the BML diet contains all of those? "
I'm not sure where you are finding your information or how long ago it was written but most of the widely used and well known glider diets use at least one if not all of those ingredients in the recipe.
There is one the highland diet that doesn't use honey in the diet or even as treats but it does use applesauce and yogurt. I don't believe this diet is a popular or widely used diet.
"But my question is, isn't honey, apple/applesauce, and yogurt not good for sugar gliders?"
Really the answer depends on who you ask. Everyone has opinions on glider diets but they are just that, opinions.
Scientifically we really don't know what gliders dietary needs actually are. The diets we use now we believe are balanced and provide essentials we think they need to thrive.
Shelly Sterk is actively trying to find what gliders dietary needs really are through scientific testing. But it could take years to find any conclusive answers from the testing. You can read more about the diet study and the studies goals on her website http://www.sugargliderfoundation.org/testing.html
Shelly has fed her personal gliders Bml for years and is the poster child for following the diet to the letter.
There are 2 diets I personally recommend 1 bml snd 2 critter love.
BML is affordable, easy to follow the recipe and easy to make, it's consistent, and you can find the ingredients locally.
Critter love is affordable for a certain amount of gliders, easy to follow recipe and also consistent however it requires more freezer space and preperation time and can feel overwhelming when first starting this diet.
Both diets have been lab tested and both have been widely used for a long period of time.
when chosing a diet consider the cost and can you afford to consistently feed the diet, ordering online vs buying locally, preperation time, storage space it takes for the diet and finally.....
It all boils down to what the gliders will eat the best. You may decide on one diet because of all those reasons but your gliders may not eat it ,if they don't eat it, it does them no good.
If the gliders are currently being fed a well known widely used diet you might consider keeping them on that if they are eating it well....