In on-screen canon, you are correct, just one appearance.
However, โDie Standingโ by John Jackson Miller is an official #StarTrekDiscovery tie-in #trekbook. The authors of those books are given access to the showโs bible.
Miller was tasked to write about #Geogiouโs journey of adaptation to the Prime Universe that took place between seasons 1 & 2 of #Disco. Emory #Dax was a key character in that transition. So I have been hoping to see Dax onscreen in S31.