I finally finished levelling my alchemy, and decided I wanted to be a Transmute Master. After farming the mats for the Primal Mights, I realized that I barely ever transmute anything (like once every two weeks) and would rather be an elixir master since I make elixirs more than anything else. I was just gonna sell the 4 Primal Mights (since it took me only two days for me to farm and they cost about 250g a pop) but I decided to keep them just in case I changed my mind again.
So then I quit the transmute quest and looked up the quest for the Elixir Master quest on Wowhead so that I could farm the mats ahead of time and be ready to hand them in as soon as I got the quest from the NPC. I had all of the mats for the quest except the Essence of Infinity I needed from the Black Morass. After running the Black Morass three times and not getting one drop, I decided to look on Wowhead again to see if maybe there was another way to get the essences. I found out that you can actually just finish the transmute quest, unlearn Transmute Master for 150g and then pick up the Elixir Master specialization from another trainer. This was no problem for me since I already had the Primal Mights.
As I returned to Zarevhi in Stormspire, he no longer had the Transmute quest for me. And neither did the quest giver for the Potions Master, or even Elixir Master. And yes, I do have low level quests tracked.
TL;DR version: Master of Transmute is bugged and Zarevhi won't give me a quest.
Sorry if I posted this in the wrong part of the forums. I figured bug report would be a good place to go since this seems like a bug to me (and apparently, an often occurring one). Thanks to anyone who takes the time to read this and offer any help or suggestions.