Recover My Hacked Gmail

My long-standing Gmail account was taken over after my ex gained access to my phone. He replaced every 2-step verification method with his own information and even set an Outlook address as the new recovery email. I’ve already filed a report with Google but, so far, their automated flow keeps looping without restoring control. Because all backup numbers and secondary emails were removed, I’m locked out completely.

The account holds fourteen years of irreplaceable photos of my children, as well as the verification messages that drive my WhatsApp. When I activated a new phone today, the WhatsApp sign-in code landed in the hacked inbox, so he now controls that too.

What I can provide:
• A collection of older emails sent from or to the compromised address that prove ownership.
• The exact Outlook address currently set as the recovery email.

What I need from you:
1. A safe, legal, and effective path to regain access to the Gmail account (and, by extension, the linked Google Photos and Drive content).
2. Guidance on reinstating proper 2FA—preferably with an authenticator app and fresh backup codes—so this cannot happen again.
3. Help unlinking the intruder from connected services (WhatsApp is top priority).
4. A short, plain-language set of steps I can follow in the future if my account is ever threatened again.

Please outline the approach you would take—whether it involves advanced use of Google Account Recovery forms, escalation tactics within Google support, or other recognised methods—and the estimated timeframe for each milestone (initial access, full recovery, security hardening). I’m ready to start immediately and will be available to supply any proof or real-time verification that Google may request during the process.