All Industry participants in FIM competition signed an agreement to the effect that FIM was the exclusive sanction for World Record affairs.
The FIM acted within their rights as per the business agreement.
Today you can claim all the World Record status you want and unless you have a signed agreement with them, they choose not to bother to challenge it.
SPEED SECRET
In the glory days of my youth, I set the undisputed World Land Speed record for Bowling Balls. I did it under the "Forgiveness is easier to get than permission plan." and it was witnessed by members of the U.S. Department of the Air Force.
They certainly had the credibility and necessary skills to accurately measure the speed.
To this date, 40 years later, I have never heard of a challenge. LOL