Hi, this is GitHub related, and your guy's organization is not verified on GitHub. You can do it like these:
Verify the organization via GitHub (gives a badge): https://docs.github.com/en/organizations/managing-organization-settings/verifying-or-approving-a-domain-for-your-organization
Verify the organization via GitHub Pages (restricts who can and can't publish on your website): https://docs.github.com/en/pages/configuring-a-custom-domain-for-your-github-pages-site/verifying-your-custom-domain-for-github-pages
Thanks!