@ndeadly here's what I hope to be my last message regarding my issue.
I met with my brother today. My controller didn't connect to his switch. His controller connected but wasn't responsive to any button. It was the same when he tried on his switch. I told him about the update you sent me and it worked as a charm. So I was in a situation where I have at the end resolved only my brother's issue
He then asked me about the small hole in the back of the controller next to the sync button. I downloaded the wii u manual and found out it was called the "reset" button to use, I quote: "in case the controller is not responsive".
With the help of a needle, I pushed for 15 seconds (random number, just sounded good enough) then retried. Hallelujah!!! It is paired and working again.
I think the thing to investigate would be what made it irresponsive ? Just to avoid such cases in the future.
Thanks a lot for your support and the updated version, it helped a lot. My son and I are very grateful. Keep up the good work and God bless you.