Jagan, I just caught your posting. Nice job of investigating. I am presuming that the Beaufighter navigator was referring to the B-29 "Gone with the Wind". My friend, an ex-159 Squadron Liberator flight engineer, was impeccably honest in everything he related to me, as best I can tell, so either there was a cover-up ordered to keep any word of the downing of a US bomber by a British aircraft from enraging American personnel, or else the navigator was spinning a tall tale.
A cover-up is a possibility, though we probably shall never know the truth. I say "possibility" based upon another incident from just over a month later, in the same theater of war. On the night of 22-23 January 1945, RAF 358 Squadron sent eleven Liberators from Digri, then its West Bengal, India, base (about 65 miles west of Calcutta), all the way to northern French Indo-China on the squadron's very first Special Duties op (dropping supplies to anti-Japanese forces in an area near Hanoi controlled by the Japanese). The British purposely did not tell the Americans about this op because there was a fundamental bone of contention between the Americans and British on how to deal with postwar FIC. The US favored backing Ho Chi Minh and independence from France, while the British wanted French colonialism to be reestablished.
So, serious bad blood existed between the British and American high and mighty, and this would explain why the British withheld any info on this op from the Americans. The RAF believed that permission to use American bases in southern China would have been denied, and the British didn't want the Americans to know what their intentions were. Thus, the Americans were uninformed that the Liberators were being sent on the long, direct nighttime flight from India to FIC. Both the outward flights and the return flights had to pass over a portion of southern China to reach northern FIC.
The weather to the target zones was horrendous that night over Burma, and the drop zones in FIC were obscured by heavy cloud. Three Libs failed to return. There is some sketchy evidence that at least one of the three was shot down by an American P-61 night fighter, and that a cover-up was ordered to prevent the sowing of widespread discontent among British forces.
I personally think that two of the Liberators crashed in the Chin Hills on their outward legs, in Burma, after failing to penetrate a dangerous weather front. It is at least possible that the third Lib to be lost, over northern FIC, was purposely shot down by the Americans, in order to make a statement.
The locations of the first two crash sites in Burma were only a few miles apart and along the route they were scheduled to fly to reach FIC. And the crash area was nowhere near where American P-61s would have patrolled -- supposedly the region was over four hundred miles from the nearest US fighter base in China and well outside not only the range of roving American night fighters, but also the area of their operational command. And, per one book source I've seen (not that it's reliable info), no bullet marks were found in the Chin Hills wreckage of the two Liberators. It is much less likely that the bombers crashed on their return legs due to American night fighter damage far to the east, over FIC or China.
The third Lib went down over northern FIC for reasons that have not been clarified. If downed by the Americans, it certainly is reasonable to conclude that a deliberate attack was due to a genuine case of mistaken identity in challenging weather conditions at night.
If there was a cover-up, it was fairly complete, and successful; sealed lips were in everyone's best interests. To the present, the only primary references to a possible cover-up that have come to light can be traced to a 27 February 1945 private letter from British General (Brigadier?) Carton de Wiart VC, senior British representative with General Chiang Kai-shek. Allegedly, de Wiart was told of a shoot-down by General Claire Chennault.
Countering the argument that the B-29 was downed in retaliation is the fact that the date of the B-29 loss was about one month before the Liberator losses. Thus, it predates the alleged downing of one or more British B-24s, so it would not have been a case of bad blood in response to any rumors of a deliberate American attack upon RAF aircraft. Still, the Beaufighter action in downing the B-29 could conceivably have been based on other bad blood, even if the Beaufighter airmen were acting upon a rumor.
I haven't even seen the de Wiart letter, and for all I know there is other primary evidence of a cover-up of the to be found, but I have my doubts.