I finally seem to have hit a groove with mine. I disassociated it completely from all of my devices and my withings app. Rebooted my devices and only associated it with my iPhone 11 Pro. Now it pop...
I finally got it to work by choosing the "Disassociate this product" which gave me the option to disassociate it from other accounts (?) As soon as I did that, I got the "Pair" request.