When a translation is published, Content translation updates the interlanguage links on Wikidata. However, this update process may take some time to be visible in Wikipedia pages due to caching. This delay may cause users confusion to see that the page still appears as missing.
Currently, Content translation forces a purge of the newly created page to make sure that the interlanguage links are updated there. This ticket proposes to also do a purge for the page in the source language. In this way, we make sure that the user will see the updated list when checking the original article.
While the issue may still be present when the user checks a version of the article in a completely different language, the source and target languages seem the most likely for users to check.