Military acft don't carry CVR or FDR.The size of the debris field looks pretty small. The fire very intense. Not sure even the flight recorder or cockpit voice recorders would even survive. Aircraft to tower recordings my be all they have, beyond eye witnesses.
The B-52 has most of the ejections seats ejecting upward and they are zero zero seats. There are two seats that eject downward. There is a minimum safe altitude for these seats (long time, but IIRC it's about 200') But the ejection sequence takes a bit of time to initiate and complete. There simply might not have been time for that sequence to even begin.
At that point in the takeoff I don't believe they were at 500 feet. No time to initiate the eject order or pull the handles. If the gunners seat was left after the gun was removed, best case could have been 4 to get out. Oviously that didn't happen. As a Crew Chief, was my assigned acft for a while.
RIP "And touch the face of God".