The specific error code #2643145 is a generic "account restriction" that almost always indicates a security or trust issue. Your actions, while legitimate, triggered what's known as a velocity flag. You did too much, too fast, on a brand new account.
New Account Behavior: A brand-new account is typically dormant for a while. A real person would not create a profile and then immediately create a business page, an ad account, fund it, and launch a campaign all within the first hour. This rapid sequence of events looks exactly like a bot or a malicious actor setting up a throwaway account.
The Problem: The system flagged your account as suspicious, and the Persona verification process is what’s meant to clear you. When it failed for some reason, the system's decision became final, at least from the automated perspective.
What You Should Do Now
Stop All Activity on the Account: Don't try to post, like, or watch Reels on that specific account anymore. Continuing to interact with it while it's flagged can sometimes make the situation worse.
Focus on the Grievance Officer: You're on the right track. Standard Meta Business Support is notoriously unhelpful for this specific issue because it's a security flag, not a simple bug. Your only real path forward is to escalate to a higher authority, and the Grievance Officer is the correct channel. In your communication, be concise and state all the facts, including the untouched balance and lack of any policy violations.
Regarding the Refund: The good news is that if the ad account is permanently restricted with an unused balance, Meta is legally obligated to refund you. You'll need to formally request this through the support channel, but it may take some time. The fact that the balance is untouched is a strong point in your favor.
The Future: How to Avoid This
If your father's account is permanently lost, you will need to start over, but this time with a completely different strategy to avoid the velocity flag.
Warm Up a New Account Slowly: Create a new account and let it sit for at least a week. Have the account "act like a human" for a few weeks—post photos, add friends, and interact with groups before you even think about creating a business page.
Stagger the Setup: Create the business page a few weeks after the personal profile is established. Wait another week or so before creating the ad account, and then wait a few more days before funding it and launching a campaign. This staggered approach makes your actions look authentic to the system.
This is an incredibly frustrating situation, but it's a known flaw in Meta's aggressive security measures. Your best bet now is to formally escalate the issue while planning a slow, deliberate ramp-up for a new account.