Oxmyx is a misspelling

<TGE> Darxide

Before we get to that point, I just want to point out that Oxmyx is a misspelling. It should be Okmyx as seen on-screen. https://memory-alpha.fandom.com/wiki/Bela_Okmyx

General Mortars

However, the spelling as it appeared in the official database is Oxmyx.
https://web.archive.org/web/20180117201931/http://www.startrek.com/database_article/oxmyx

<TGE> Darxide

Incorrect is incorrect.

<TGE> Darxide

And to clarify my above comment, there's a long established precedent in Trek lore: Anything that happened on screen has always trumped any other source for sake of canon. This has included official print sources as well because they have been known to be wrong in the past. I'd consider a website (especially one only viewable on the Wayback Machine) to be a print source.

A future on-screen episode may retcon past information, but print material does not.