A fix just rolled out in today's catalog update, we had to fall back to a file version detection if the registry version detection does not work. This seems to have been a problem since they switched over to the MSI based installer. We modified the existing updateid, so you will want to republish https://patchmypc.com/when-and-how-to-republish-third-party-updates the Nextcloud update to make this change active, otherwise all future releases should be fixed as well.