Existing documentation URL(s)
https://developers.cloudflare.com/turnstile/reference/supported-languages/
What changes are you suggesting?
I believe the Google Form linked needs to be amended and/or a new form is made to allow users to submit requests for new languages. This user on the Community forum wishes for Latvian support, but couldn't find anywhere to request it https://community.cloudflare.com/t/add-latvian-language-to-turnstile/760031/4
Additional information
This page here has a note that says you may submit feedback on new language/translation errors.
However, the Google Form link doesn't provide an option to request a new language (as the documentation suggests). It only allows one to submit feedback regarding a specific language's translations.