Hey! I also have a 2021 BS Outer Banks and have also experienced the same thing.
So... I've had 2 episodes of a powertrain fault where the transmission down-shifted suddenly, and the vehicle lost speed and power. The 1st time was at 70 mph on a highway (scary- also had vehicles on my tail), and...
I honestly can't make out the noise in your videos, but I have been experiencing something similar on my 2021 BS Outer Banks. I describe it as a "chuffing" sound at 1500 rpms during acceleration and braking. (Video attached.)
So... I've had 2 episodes of a powertrain fault where the...