I’m confused: brand registry question

I found a product I wanted to sell. It’s made by Company A, a reasonably well know name in its niche. The product ships in Company A branded packaging.

I found one existing listing for the product. The listing was created by Company B. Company B is a brand registry participant. Keepa shows they have 0 of this item in stock. BUT Company B registered the Company A product as their own. It’s definitely the same product, they even used the same catalog pics in the listing.

Because it is registered I had to apply to sell. Of course, I had the correct paperwork, etc. I was turned down. I don’t mind being turned down, but how can Company B register Company A’s product as their own? I did some digging and they are definitely reselling. They’ve registered hundreds of Company A products, so they have basically locked out the competition.

Is this kosher? I’m a little bummed because it’s a cool product.