Ask HN: Locked out of Google despite knowing password and having email access

I'm trying to recover my Google account. I know the password, but unfortunately I've lost access to the phone number where Google keeps trying to send the verification code. It used to just ask me to fill in the missing digits of the number.

I still have access to Gmail through a third-party Android email app, where I can send and receive emails normally, but I can't sign in to my Google account anywhere else. The account is old, I never set up a recovery email and I haven't used it outside the email app for a long time. I've tried various devices, networks, and VPN combinations without success.

Google's own recovery help says:

"Tip: We may send a verification code to the email address on the account you're trying to recover. This way, you can get the verification code if you have access to your Gmail inbox through a third-party email client or email forwarding."

But I've never been offered this option.

After multiple recovery attempts, I eventually got to a step asking for an alternative email address. I provided one and verified the code Google sent, but the final screen told me to reply to my Google support contact. I don't have one.

I found this HN thread where a Google employee (`luka`) helped someone in almost the exact same situation:

https://news.ycombinator.com/item?id=49744286

Unfortunately, I can no longer reply to that thread.

Does anyone know how to get a similar escalation or another way to recover access?