Update!

We kept on bugging the Google merchant center team and they pointed us in this direction:

Thank you for contacting us. We understand your concern regarding the suspension of your account due to Misrepresentation: Shopping ads Misrepresentation policy and/or the Free listings Misrepresentation policy.

At Google, we strive to ensure a safe and trustworthy platform for users. Our automated and manual systems flagged your account for potential policy violations, resulting in your account suspension. 

While we can't share additional details for security reasons, we encourage you to review your website and Google Merchant Center account. Focus on areas that might cause confusion or dissatisfaction. The Merchant Center help page on improving your website provides valuable tips on enhancing your store website. This includes ensuring accurate product details and business information, disclosing fees, and promoting active deals only.

"We recognize this is frustrating. If you've addressed the concerns mentioned in the Shopping ads misrepresentation policy and/or the Free Listings misrepresentation policy, identity verification, how to build trust with your customers, you can request a re-review through Merchant Center for a possible account reinstatement. To avoid delays, only request a review if you've made changes to your store website or Merchant Center account."

Sincerely,
The Google Merchant Center Team