What should to do if the Wayback Machine (archive org) could not find a saved copy of the website?
You could try searching smaller national web archives such as Trove or PRONI. But this is not step number one.
The first thing to do is to turn to different IP Search engines.
For example, UrlScanIO (urlscan.io) has a "Content" tab on the page of each domain, where you can see the text of its main page. And a "DOM" tab, which displays the HTML code. Sometimes this way you can get to see what the site looked like a few months or even a couple years ago (different for each site).
Netlas (netlas.io) also has the html code for each domain's homepage available (right on the results page). Before searching for a site, you can select the date of scanning (saving the site server's response to the Netlas database), there are several options from 2022 to 2025.
For easy viewing, copy the HTML code from the body field, remove the \t \n \r characters from it, and copy it again in any online HTML Viewer.