As a company you are failing to meet the terms of service as seen on the following page:
Section 3.3 User Wallet
- © use the private key backup functionality provided by the Brave browser and safeguard your backup private key file as you would safeguard other important financial information.
This is impossible, as that backup area says, “The funds in your Brave wallet are virtual and not required to backup. It’s available for you to spend exclusively on this browser.” Also the only option that becomes available is Uphold if someone is able to reach 25 BAT.