I have another update but not a resolution. To add, this is the keyboard I have.
https://www.microsoft.com/en-us/d/surface-pro-keyboard/8tc5c5t5g9dm
When I purchased the keyboard this keyboard wasn't available. Only the business version was available but at the time it said it was compatible with a Surface Pro 11. Now it doesn't say that. I don't know if both keyboards are the same but the serial numbers are different. Moving on, Microsoft support for business did reply back to my concern. After several tests, it was determined that the keyboard was bad. The test was to put it in UEFI mode and if the keyboard didn't respond, the keyboard is determined bad. The keyboard did not respond in UEFI mode. I asked the support agent if they could do the same tests on an identical setup that they might have and the support agent said no further testing was necessary, the keyboard was determined bad/defective.
I spent a week doing further testing on my own and I don't know how I got from the Surface Pro sitting overnight to WHEN I folded the keyboard over the screen but that is what I verified. Here is what I verified many times. If I fold the keyboard over the screen/display within a minute after powering off, the keyboard will not respond when turning back on. I guess a clarification needs to be made here. When the keyboard is not responding the Surface Pro is in tablet mode also. You can tell it is in tablet mode by the size of the icons in the taskbar, the icons are a little larger. Once the Surface Pro is in tablet mode, I know of no way to switch it to desktop mode other than unmounting and mounting the keyboard.
This is where I am at. I don't know if anyone else could duplicate the concern. I don't want to return the keyboard and repurchase if it isn't going to fix anything. I am also willing to tolerate not folding the keyboard over the screen if that is how it is. It would be good if the moderator would locate a Surface Pro with this keyboard and see if they could duplicate and concern. If they could, it could be possible that Microsoft could do a firmware update to the keyboard or Surface Pro instead of having people returning their keyboard, Surface Pro or both as defective.