Had you bothered to read Sen's work rather than quote one section of it you'd notice the very narrow timeframe from which the average is obtained. This is massively important because the period in question was a drought period seeing a huge reduction in yield per capita.

It wasn't just a 'little' lower is was substantially so.

The pre-drought yield per capita was 0.193, but for 1943 this was now 0.138 which is a substantially reduction far greater than either you or Sen show.

However let's go back to your initial statement on the matter.

"Btw Bengal itself had produced an equivalent amount of crop in 1943 as it did in 1942, meaning there shouldn't have been much of a famine, even with the refugee influx."

You said 1942 was equivalent to 1943, yet even in Sens work this is clearly not true.

According to Sen in poverty and famine p. 61 the index of foodgrain avilability for 1943 was 109 but for 1942 it was 130.

Yet according to you these are 'equivalent'.

So which is it?

They destroyed crops near the bay of Bengal, so that if the Japanese army did in fact invade from there, they couldn't use the rice to feed their own troops. This was supposed to be limited in scope, "however, evidence that fraudulent, corrupt and coercive practices by the purchasing agents removed far more rice than officially recorded, not only from designated districts, but also in unauthorised areas, suggests a greater impact". [Weigold 1999, p. 67; J. Mukherjee 2015, pp. 62, 272; Greenough 1982, pp. 94–95.]

That's wild conjecture with no hard numbers, even Sen suggests that some of this alledged destroyed rice was used to feed famine victims but since you seem to have an aversion towards numbers.

40,000 tons confiscated or destroyed from the denial policy.

They created an entire blockade in the bay of Bengal, severely limiting any transportation of food, supplies, equipment and crucially, even fishing. Additionally, the army took no steps to distribute food rations to make up for the interruption of supplies. [Bayly & Harper 2005, pp. 284–285.]

It was the Japanese who blockaded the Bay by occupying Burma and attacking allied shipping in the Bay and Indian Ocean.

The army did take steps to distribute rations, Wavell says as much, not only that but Churchill even advocated for the use of the military to help.

Let's see what Sen has to say about your sources and your view in general. I shall quote him

"Madhusree Mukerjee seems satisfied with little information."-Amartya Sen