Wikimedia Foundation refuses voluntary union recognition, hires union-busting law firm

A few months ago I cancelled my donations due to them firing a group of workers who stated their intent to unionize.

Where they actually fired? From skimming your linked article it was more of a restructuring, moving them to different positions. The restructuring might be ill advised, though I could not find real information about any connection to the union topic, besides someone from the community claming that, without further information on that connection.

Find this reference on Reddit.

including those laid off, since some are still hoping to find jobs elsewhere at the WMF, and others are depending on severance pay

Am I too european to understand this? If they “get jobs elsewhere at the WMF” this is not a layoff, is it? I know the US has nearly no worker protections, so maybe that makes it a layoff. Do they need to interview for these positions again?

If this were something other than Community Tech, maybe I could convince myself it’s all just a coincidence. But the WMF has been on a generally upward trajectory at avoiding decisions that will piss off the entire community. “Don’t disband CommTech” might as well be the "don’t mess with the pancreas"of WMF governance. The only explanation for the WMF doing this—not just reörganizing but outright laying off the team—is that they are so determined to prevent the union from becoming official that they are willing to risk the massive community blowback (which, from a corporate-brain point of view, is a greater downside than the five people left jobless).

That paragraph I don’t understand. Why is union busting the only explanation?

From one of the comments of that Reddit thread:

the union was apparently formed exactly 90 days prior to the layoff announcement; under california state law (where they are located) “a termination within 90 days of protected union activity creates a rebuttable presumption that the termination was illegal retaliation”

I think that is an interesting detail here, though I have not bothered to go through the sources for this.