The error that caused all this:
SERVER DETAILS Web Server: LiteSpeed X-Powered-By: PHP/7.3.33 IP Address: 5.22.249.133 Hosting Provider: CJ2-AS, NL Shared Hosting: 500 sites found (use Reverse IP to download list) Title: WordPress rsaquo; Error
See: https://urlhaus.abuse.ch/url/2118874/
Where detection and malware was missed completely:
https://quttera.com/detailed_report/www.duchessadimotta.com
Where at least the install error testpage was mentioned, but malware not flagged: https://sitecheck.sucuri.net/results/www.duchessadimotta.com/wp-admin/setup-config.php
More sites out there where this was being abused for PHISHING → https://maltiverse.com/search;query=404testpage4525d2fdc;page=1;sort=creation_time_desc
polonus (volunteer 3rd party cold reconnaissance website security-analyst and website error-hunter)