id check home button flex that attached to shield, does your old screen work with home button. also back up and fully restore phone. did you use enough heat to pull away the home button? check for any type of damage.

i would swap out the whole d-pad , i couldn’t imagine it being more then a few dollars for the part, the rubber parts are conductive. other wise since its not a flex cable and the d pad is actually on the board. a new board isn’t a bad way to go. if you think its worth it. 3ds are pretty cheap and a huge upgrade

i would contact huawei support and see if they have an older version of the stock rom you can flash. then flash it. then maybe work your way up slowly to the newest update

any type of damage to the home button pins can cause issues, will it boot with no home button installed? also know that if home button is damaged the iPhone 7 series can’t have a new home button.