Solving Gemini API key errors in Discourse

How do I connect Google Cloud AI for Discourse AI.

I tried the steps mentioned in the post

but GCP interface has changed.

I tried what’s mentioned at

But still encountering the following error

For now I’m using a workaround (Google Cloud Run → vLLM) but latency is very high with that method.

Can someone tell me how do I fix this error? I want to use one of the AI models available on GCP as the default LLM.