I can't find the ID in any emails. What's the next best step to retrieve it for my suspended account?

If you've exhausted email searches, try contacting Google Business Profile support directly. While access is limited for suspended accounts, explain your situation and request the ID for appeal purposes. Be prepared to verify your business ownership through documentation. You can find the support contact form through Google's help center, searching for 'Google Business Profile Support'. Be persistent, as response times can vary.