iPad2 Activation Error 9.3.5

I am unable to activate iPad2 (32GB, GSM) factory unlocked.

iPad was working 48 hours ago, with some lag issues I thought of updating to latest f/w with iTunes on Mac. Since then it is stuck on activation screen.

I have attempted several steps as below:

1. http://techbakbak.com/updating-ios-93-solve-ipad-2-activation-error-update/
2. Apple UK support (force restore,force update, etc)
3. To force update and/or force restore with 9.3.5 ipsw

   Latest version File name iPad2,2_9.3.5_13G36_Restore.ipsw

4. Tried on Windows 64bit and Mac, both has latest iTunes version.
5. Tried with 3G activated sim

   It searches for network but in a moment says "No Service". Tried alternate sim as well which are working 3G on mobile.

Additional steps performed:

• Confirmed with Apple support that iPad is not blocked(network operator or apple id) from their end.
• Local Apple service centre are not able to diagnose, as device is not on Home screen and replacement costs as much as new iPad.
• Tried different cable, but stuck on activation screen on iTunes.
• Under account appleid.apple.com , iPad 2 shows as version 9.3.5
• I had disabled location service before I started to update iPad in the first instance.
• iPad is not physically damaged.

Activation steps available on iPad 2 are as following:

• Slide to Setup
• English
• Choose region (Tried US, UK, Australia, India) - I am in India, iPad purchased from UK
• Choose Keyboard, tried random keyboards
• Choose wifi, tried alternate wifi and with dns 8.8.8.8
• Activation error ( see screenshot below)

iTunes activation screenshot

iPad activation screenshot

I would appreciate all the help I can get to bring my iPad up & running. Masters, users and suggestions are welcome