Redacted excerpt; full evidence withheld.

$ cd <guest-path> && pwd && ls -la && id -u && python3 --version && cat README.md 2>/dev/null | head -c 6000
exit: 0
cks that could not fire on any site, because the markup they
  read was discarded before they ran;
- every PDF check, dead from the moment JavaScript rendering was switched on;
- a raw-versus-rendered comparison that had been comparing a document against
  itself;
- **a failed PageSpeed run that reported as a clean bill of performance** —
  the API returned a quota error, the integration swallowed it, and the report
  came back with no performance issues at all;
- three "checks" that were not checks, only sample data left in a test file.

[excerpt truncated]