OP: "I've been trying to register my brand for months, submitting information from tax documents, state filings, trademark office, etc. as proof but every time I submit more information I'm rejected."

All of that is what it takes to own a business. Amazon wants you to show that your brand really exists in the real world.

Amazon wants to see your product line, your brand name permanently affixed to the products, your GS1 UPC's registered in your brand name, and any COC that may be necessary to sell in the USA.

OP: "The emails give absolutely no context about why the rejection is happening"

Correct, this is how Amazon thinks. When you were in High School and turned in an assignment, the teacher would review the work, and return it saying, “X, Y, and Z are missing, go fix it, turn it in again, and it will be correct”.

Now when you are in college and turn in an assignment for review, the instructor returns it and says, “it is not right, do it over”.

Can you see the difference? In High School the student is told what to do. Basically, the student has to use no internal thought process. Now in college, the student is told nothing about how to correct the situation, what may be missing, or what should be omitted. A much high thought process is required to solve the problem. This method Forces deep self-introspection before a second submission is turned in.

It is quite evident that Amazon EXPECTS and REQUIRES the Sellers to show they have given deep thought to the total situation before applying. As you found out, Amazon is not going to tell you the corrections that need to be made.

OP: "I've confirmed our information with the USPTO, I've confirmed with our accounting firm, I've confirmed with our CEO".

Not sure what good having an Accounting Firm is when you can do everything yourself online.

You can do the same USTOP test Amazon does and get the same result as Amazon. Just enter USTPO Registration Number ?????????? in the google browser and see what comer up. It is so easy am Amazon Bot can do it. Does your company come right up or not.

OP: "How do I actually get through to a real human that can tell me what the reason for the rejection is?"

There isn't a real human. With 9.7 million registered users on the site, do you think one more holds an importance? Probably not. So, Amazon uses bots to check applications. Those that can be verified or really exist off site have no problem. Those who want to try and start a brand on the site, have a long uphill battle.

OP: "...We have false sellers reselling our product, and we've been trying to bring our products to the marketplace since the midpoint of last year".

That does happen, and there are way too many reasons why it happens to go into here. However... the solution is below.

OP: "...We have the listings, but you basically can't do anything until you register the brand. Help?"

Seller support will be of no help.

However, you have had the solution at your fingertips the whole time. Your USTPO Registration gives you legal rights in the USA only, so use them. To stop other from selling under your brand, send the USTPO documents to Amazon Legal Office in Seattle, in a well-crafted letter by certified mail. They understand your problem and can have others remove from the listing. Takes about 3 weeks or less.