WHITE SCREEN OF DEATH FIXED WITH ELECTRICAL TAPE!!!
Thanks to AGorman and THX992 for the help. The white screen on 2 of the 4 Blackberries is back to normal, all because of 2 well placed slivers of electrical tape.
Here's that we did:
I placed 2 thin slivers of electrical tape on both sides of the fragile ribbon cable of the LCD screen. Apparently, this little ribbon cable is being cut or crimped too much over time by the case and/or circuit board. Placing tape on both sides lessens the pressure on the ribbon cable.
Little slivers of electrical tape fixed 2 of my 4 busted Bold 9700s. I'll fix the rest tonight. This is what I mean by poor design and defective hardware from Blackberry.
I hope this helps other people...