https://platform.openai.com/docs/models#gpt-4o-audio
They should be widely deployed.
The platform web page makes a standard request to the models endpoint for your organization and project selected at upper-left. Just using web session authentication instead of API key authentication.
See that you have other models requiring payment unlock, such as gpt-4o and o1-preview in “chat”. This shows that the models API call is being made and fulfills the selection box. Check project for any limitations on models you may have placed before.
Sounds like you got it fingered out while I was typing… 