Not sure if Make-A-Wish cares about this sort of thing strongly enough, though, to care about this article. Well, we'll see, I guess :-)

The likely not care strongly enough to specifically strike back. On the other hand a bunch of people will hold grudes because of the article. For a lot of grant decisions of foundations good will in the broader philantrophic scene is important.

I don't think that the damage done through a single article like this is high but there risk with attacking other people. If you frequently attack other people doors close in unexpected ways that otherwise would be open. Your article likely wouldn't use a lot if you wouldn't name the "Make-A-Wish Foundation" specifically but focus on the story of Disneyland. At the same time that would reduce the amount of grudes that people will hold as a result.

When writing articles like this, keep in mind that there are real people working at the "Make-A-Wish Foundation" that are stakeholders.