Chosen Solution
I have been repairing electronics for years. Never had any issues with iPads until recently, home buttons stop working after digitizer replacement. There is no damage to the home button or the cable or anywhere. Anyone else having this problem? Or have found a solution?
It could just be an alignment issue, is the metal part of the home button bracket (which is the contact for the button) aligned with the center receiver of the home button?
Look at the back of the home button. There should be a tiny black dot in the center of the switch. If all you see is amber that dot has fallen of and the switch will not work when installed.