I replied to that same old thread that you are talking about:
https://retropie.org.uk/forum/topic/22692/fake-8bitdo-sf30-pro-way-to-get-working/21

As I mentioned over there these controllers work just fine over Bluetooth on my Linux PC, but aren't detected over Bluetooth on the pie. Thought I'd drop a comment here also so I can see if any progress is made by anyone else.

After JsTest, when i press the buttons, as i said the corresponding number is blinking ON
A,X,RShoulder = 1
B,Y,LShoulder = 3

Any ideas else then s*tty controllers?

Got it thanks again for all the help. I guess this brand is more commonly referred to as a shenwen controller and that's what the pi recognized it as.
After installing the PS3 drivers, I used this guide to help:
https://raspberrypi.stackexchange.com/questions/54522/retropie-ps3-controller-over-bluetooth/54630

I appreciate the help as I'm now able to play from the comfort of my couch, as opposed to a folding chair I had set up in front of the TV.