That version is only valid until 31.12.2020. Thinking it may have been an old link, I had a look another look going through the UCI website and it's still the same version.
It might explain why the commissaire stopped him riding it.
I need to get out more
The list is here, and Ribble doesn't appear (their cx bike at least)
Pretty significant oversight really https://www.uci.org/docs/default-source/equipment/liste-des-modeles-de-cadres-et-fourches-homologues---list-of-approved-models-of-frames-and-forks.pdf