Hi I think I found out the problem. There is a Piezo vibration sensor and it's oxidized. Have you seen at which position the sensor is at yours? I think there could be some with the sensor on the right side. Info the sensor is 20mm diameter.
Yes it is possible. But its very important to reassamble the kaptontape. If you forget the kapton tape you have a grounding problem and youre touchscreen wont work properly
I used double sidded 3M Scotch Tape and its working fine. But its very important that you reattach the Captontape of the Homebutton and Flexcables in the right Position. Because those Cables have some groundingpoints on their backside. If those groundingpoints have contact with your LCD-Backplate the touch is not working properly.