Project Import Settings for Developers - GPC project Permissions not working

I am trying to grant our developers project import permissions so that billing can flow through the same project and API keys can be tracked in the dashboard. I have assigned the following roles to the test account at the project: API Keys Admin, Editor, Service Usage Admin, and Vertex AI user; however, this test account is still unable to create any API keys and attach them to a project. Please advise.

As an ORG admin, I am able to import projects, but I would greatly prefer not to grant overall org access to every developer.