(It's generally helpful to start from the assumption that, if something completely isn't working for you, that's not everyone else's experience.)

Add Item by Identifier should almost always work, and if you have other examples, you should provide those so we can look at them.

The issue here was that the provided data was in a form we'd never seen before in over a decade of using Crossref metadata. I've fixed this, so if you have automatic translator updates enabled, it should work for you shortly, or you can update translators from the Advanced pane of the Zotero preferences.

"Almost always work" though?

Yes. You can make snarky comments that will discourage people from trying to help you, or you can believe us when we tell you that this this is a basic feature of Zotero that has existed for over a decade and works for most identifiers that most people enter, and we can work together to debug identifiers you've found that don't.

The DOI above, as I said, was in a format that we've never seen before. That's now fixed.

That ISBN is for a self-published book — published on Amazon (specifically CreateSpace, now part of Kindle Direct Publishing). So, obviously, it shows up on Amazon, and it shows up on LookUpByISBN.com, which is, best as I can tell, a random site that — as it says — searches Amazon (and has trouble doing so, because Amazon has strict limits for external searches). It's not registered in the Library of Congress, Open WorldCat, or the couple other sources Zotero checks. Amazon doesn't provide an open way to search for books. We could consider doing an actual web search on Amazon and scraping the page as a last resort, but there's a decent change such requests would be rejected and possibly even get people temporarily blocked from Amazon. Google also puts restrictions on the use of the Google Books API that make it theoretically unsuitable for use in Zotero.

So the current answer to your question is that Add Item by Identifier will work for any DOI registered in Crossref or a half-dozen other DOI registrars, any ISBN registered in the main databases, and any PubMed ID or arXiv ID. When it doesn't work, doing a web search for the identifier will usually make it clear why it's not working and/or take you somewhere that you can save from (such as the Amazon product page, in this case).

We also have DOI translators for EIDR and mEDRA.