Answer
Check for multiple, conflicting Page Configurations published simultaneously for the same page — having two separate Page Configurations for Time Registration published at the same time has caused exactly this kind of metadata error, since the two configurations can conflict with each other (in one confirmed case, publishing both together broke the page with a metadata error, while publishing only one of them at a time worked, though which specific configuration a given user's context resolved to could still result in a 'Nothing Found' error for some users). Reviewing manually-configured Page Configurations for this page and making sure only one applies to a given context/company, rather than continuing to focus on caches, permissions, or profiles, is the direction that resolved this specific case.