Search for Existing Brand Names in Brand Registry?

Before spending the time or money on USPTO, lawyer fees, creating a logo and packaging, is there a simple way I can search on Amazon if a brand name is already in use in their Brand Registry? I understand there are services to research if there’s any potential legal trademark issues but I’m interested in first confirming there’s no one using this brand name on Amazon. For example, “Brand Name” might be fine to register in my state and with USPTO without conflicts, but it’s possible that someone is using “Brand Name” in the Amazon Brand Registry.

While not necessarily related, one thing that’s made me a little more concerned is that I attempted to change the Display Name of my Seller Account to be “Brand Name” and it says “Display name not available”, however I can’t find any seller with that name just by searching on Amazon.com. Perhaps there’s other possible reasons for this error?