Ask Oscar and Katie for TG&F's full contact info. The letter seems to leave this critical detail out. There should be a verifiable street address, phone number, website, and email. There should be information on the website about the qualifications of they lawyers employed by the firm.
They are asking for your signature, but no one is formally signing and agreeing on behalf of VM. This means you could be bound by the terms and they might not be.
Based on my reading, it looks like even an informal complaint, such as a review or a post at the FPA would wipe out your chances of recovering any money this way.
There is the unfortunate possibility that this is just a method to silence criticism while giving the company a 6 month head start to get away.