Missing power button, How can I turn on my device?

my nexus seven is practically completely smashed. The screen is obliterated and completely inoperable, and the back plate and battery also flew out when it broke.

I have some data on my tabet pertaining to a friend who just passed away, and I only need to access the data. I am in no way attempting to completely repair the device, I only need to know which components need to be working in order for me to plug the device into my computer and pull the data from it.

I already know exactly how to get the data off of it, but my problem is that the power button and volume rocker (both up and down buttons) flew off and were lost in the accident. The metal "button" below the plastic pieces still seem to depress fine, but with the screen broken I can only tell if the device has powered up by having it plugged into the computer, and having the computer recognize the device.

For some reason pressing the buttons are not powering the device on. Other than the battery falling out after the impact, all components other than the screen/digitizer seemed to be intact.

Are there any circuits that might possibly be severed? I once lost the power button on my galaxy nexus phone and was able to wedge a needle somewhere (I think where the ribbon connected to the motherboard) and complete the circuit, but its hard to tell what the problem is with this one. Is there any way to get my device powered on? if not, is there any other way to pull data from its internal memory?