Black screen when booting into Mac , external monitor works I've Macbook Pro (Reina Mid 2016) , Graphics: Iris Pro .

I tried to install windows 10 using Boot Camp , it seemed to work. I was able to boot into windows.It worked for about 30-40 minutes and suddenly black screen. I figured it's graphics driver for windows failing. I did hard reboot and was able to boot again. After a while resolution changed and got notification graphics driver failed. I got black screen rebooted couple of times and same thing happened and after a point never recovered. I thought , it's corrupted graphics driver so uninstalled Bootcamp windows altogether. Nothing , still black screen tried following to no avail.

1) Reset PRAM , NVRAM
2) Reset SMC
3) Drained battery and reset again
4) Able to see , on external monitor so not an issue with setup.
5) Can't see backlight , Apple logo at back not lighting up. Nothing on screen , not even Apple logo loading same can be seen on external monitor though.

Please , let me know if something can be done. I would greatly appreciate that !
I know this may sound bizarre but have you checked your native screens settings? Such as brightness controls etc?
If they are all correct, have you tried running the MBP with power plugged in and the battery removed?
Otherwise, have you tried re-seating the ribbon connector for the screen? You can find the guide here: https://www.ifixit.com/Guide/MacBook+Pro+17-Inch+Unibody+Display+Replacement/3438 
However, if this is a mid 2016 model, then I wouldn't hesitate to go the warranty route with apple and opening it up could invalidate your warranty.