I think the typical way to disable the gun was to release the oil manually and fire it before abandoning it. This makes it seem like they tried to fire it while the tank was on fire which would be insane
Curious if anyone has an excerpt.
The real story? Well, that was pretty much an exact quote from the book. The tank was hit by a panzerfaust when the crew was evacuating, causing an internal fire.
Another (less detailed) action raport from "Tigers in Combat II" by Wolfgang Schneider:
"27 March 1945: Shortly after crossing the line of departure, the 1./schwere SS-PanzerAbteilung 502 is stopped by a minefield; three Tigers are immobilized.
The same thing occurs in the attack sector of the 3./schwere SS-Panzer-Abteilung 502 (SS-Obersturmführer Schienhofen), which is advancing on the right side of the main road Manchnow Kietz. One tank -Tiger 32I - is immobilized after running over a mine; it then knocks out two Soviet tanks before it is knocked out by a captured Panzerfaust."
Just as a sidenote, Tigers were more or less prone to violent self-combustions, even during the road marches and these type of fires generally led to a total loss of the vehicle.
Battle damaged IS-2 from 57th Guards Tank Brigade in the village of Rusin, Glubczyce. March 1945. According to the Soviet records, this IS-2 was hit 16 times (no total penetration) during the battle.