I've had mine twice now where pushing the power button didn't do anything. But the phone was on - I could see the LED blinking when I plugged it in. Pressing and holding the power button did nothing, nor did a vol-down + power do anything. I thought my screen had gone out as well, and was sitting there thinking about the same as you. Then tried pulling battery and phone came back up. Was less stressful the second time.
Not saying this is your issue, as I would assume you've pulled the battery. But it may not necessarily be the screen. In any event, I would take it back to VZ as you will save your $100 deductible since it would be on a warranty claim, and there's no way they'll be plugging it in to see if you've modded. And like someone said above, if it can be plugged in and checked, then do that yourself and take it back to stock. If you can't see it on a computer, they can't either.