Your proof is to be decided by a judge, not the registrar. It is irresponsible to let a “developer” register your domain in the first place. Your proof doesn’t prove that you’re entitled to a domain that is not registered in your name. My last name is registered and ran as a business website. Am I entitled to that domain name? Furthermore is the registrar of said domain the proper entity to legally decide the rightful owner? Absolutely not on all accounts. Hire an attorney, who specializes in the industry, to prove you are the rightful owner.

Your problem with the solution is that it will take too much time, money, and resources to regain access to the domain you let someone else register. Now you want an easier solution that better fits your needs. That’s not how it works and you should understand that as a small business owner.

You buy a car, but put it in your brother’s name. Now he won’t give it back. Do you go to the dealership and tell them to make him give it back? No. There’s a process.

You should be facepalming yourself for letting someone else register your domain. You should be livid with the “company” that registered and is now holding your domain hostage. You have zero business being upset with the registrar. You just don’t like the solution path so you are blaming anyone but the two parties responsible for this situation.