I have done all of the quests to learn all of the Tailoring recipes that u learn from doing the Legion Tailoring Quest Line, however they still show up as being unlearned.

This should be fixed as of commit 45d51e7. Do note that you may need to let ATT update your known patterns cache by opening the Tailoring profession window with "Show the Profession Mini List Automatically" enabled.
If you are still finding erroneous behavior, please open a new issue with the specific pattern/recipe names you're having trouble with.

This is due to some automation Crieve did for recipes. The downside is that it added every spell Blizzard has in your profession window, even if it's hidden. This also had the effect of displaying Training Recipes which aren't learnable at all.

One of the contribs one day have to sit down and go through all of the recipes and files and eventually fix them up.