Broken Screen Unroot Relock and Flash Nexus 7

My screen broke and I have to send it away to Asus to get it fixed. I want to wipe it so there isn't a fuss checked up about my warranty.

Any ideas?
I can't access the machine and I need to this today as the Courier company is coming to collect it on Monday. So I don't have time to get a usb otg for a mouse .

Can it be done?

I think my device is on usb debugging? What the risks in using Wugfresh One click if it isnt on ?
I don't think I would have turned it off after root a couple of months ago

Thanks in advance

Famousrabbit

Flashed and Unroot and Unlocked using Nexus Root Toolkit Worked out fine just select Boot Loop

Strange thing happened which should probably be re posted somewhere. My Nexus 7's screen got a hairline crack two months ago and was refusing to take any touch input becuase of the crack. Then after flashing the device today the device started taking touch input again *strange* So the only problem is that it has a harline crack on the screen

If anyone knows anyone else who cracked their screen and had a device that was refusing to take touch input can you please ask them to try flashing it.