Moto G 2nd Gen Touch Screen Stopped working
I think your best bet would be to send it back to Motorola or a service center, because while you might try and fix your phone and get some results , there is also a significant chance of damaging your phone further.

Since the problem seems to be the screen the tech professionals might need to replace it or fix the problem in a similar manner.
You can also try to purchase the screen yourself and try to replace it , but thats really not advisable unless you're sure of what you're doing and you have diagnosed the problem correctly.

I strongly suggest you send it to a Motorola service center.
The screen can be purchased at:

(DO NOT PURCHASE THIS UNLESS YOU WANT TO REPLACE IT YOURSELF)
http://www.dhgate.com/product/1-pcs-free-hk-post-shipping-lcd-display-for/209710530.html#s1-1-1