Try the directions in this thread. It may help you. It's a forced reload of the software. I think it may work. Thus far, I've been getting a message box that said: The device does not have sufficient storage space to accommodate your selections.
Please select fewer optional applications.
At that point, I was trying to load the very bare minimum. I continued to get the message box. I just couldn't figure out why I suddenly didn't have sufficient storage space.
For the heck of it, I put the battery from my old 8700g in and tried again. I attempted the bare minimum and it went through, but then at the end it failed.
When I pulled the battery out and put it back in the 8700, it beeped signaling a low battery. It wasn't fully charged before I put it in, but it wasn't low either.
I wrote all this to say, that under this method maybe you need a fully charged battery and perhaps with the unit being in this perpetual state of nothing, it's battery draining. That could be part of the consistent fatal errors, not enough juice from the battery when trying to revive.
I'm in the process of charging up the 8700 battery and I'll try again.
Here's the thread: How do I Recover a Dead BlackBerry? - BlackBerry Forums at CrackBerry.com
I hope it works for you. And me.