There are other lines in the post that, to me, provide clarity.

First is this, the second paragraph:

> British-based employees at the Wikimedia Foundation (WMF) wrote a letter to management today (Wednesday 24thJune) requesting their right to be represented by the United Tech and Allied Workers (UTAW) section of the Communication Workers Union (CWU).

That makes it clear that this is regarding the "British-based employees at the Wikimedia Foundation". Yes, the headline does say "Wikipedia": I expect the CWU chose that because many more folks know what Wikipedia is, vs. the Wikimedia foundation.

Second is this:

> Over 1000 Wikimedia volunteers and community members have also signed petitions in support of the workers, who have networked globally under the banner of Wiki Workers United (WWU).

I view terms like "[wikipedia] editors" as terms of art: "Editor" in the Wikipedia context maps to the more-generic "volunteer" in the broader context, which is why the post is referring here to "volunteers and community members".

So, I don't see any inconsistency in the article, but I see how the current post title can make it confusing.

In my opinion, I think it would be appropriate for you to email the HN folks, to ask the title be changed to something like "Wikimedia Foundation Workers to Seek Union Recognition".