Origin of a story: The Afridis and the leader Inquilab

The call for Purna Swaraj  in 1929 led to enthusiastic participation in the subsequent Non-Cooperation movement.  One story in modern histories that emerges from the North-West Frontier Province from that time is as follows (I learned of it on twitter from @LotusTile):

Though Ghaffar Khan's own movement was confined to the settled districts of Peshawar, Kohat, Bannu, Dera Ismail Khan and Hazara, there were also a series of tribal incursions in the latter part of 1930 against which aerial bombardment was freely used.  The tribal raiders this time significantly refrained from looting villages, and with moving simplicity raised demands for the release of Badshah Khan, 'Malang Baba' (the 'naked fakir', Gandhi) and 'Inquilab' (they had heard the slogan Inquilab Zindabad, and had assumed 'Inquilab' to be another great leader in prison).

This above is from "Modern India 1885-1947" by Sumit Sarkar,  1989.  The source of this charming story is not given.

A search for an earlier source, leads one to "Pilgrimage for Peace - Gandhi & Frontier Gandhi among N.W.F. Pathans", by Pyarelal (1950).

There he writes, quoting a few phrases from Collin Davies, The Problem of the North-West Frontier, 1890-1908:

Round the Khyber and to the south live the much maligned Afridis whom circumstances have forced to become "distrustful of all mankind".  Once, however, this distrust is removed, the Afridi is said to be capable of the greatest devotion, and "may turn out to be your staunchest friend".  In appearance lean and wiry, "his eagle eye, proud bearing and light step" bespeak a freedom born of his wind-swept mountain glens.  The Afridis played a very important part during the two Afghan Wars and during the Civil Disobedience days of 1930, when the brutalities perpetrated on the Khudai Khidmatgars in Peshawar and the other parts of the Settled Districts caused a deep stir among them.

Pyarelal ends the paragraph with a footnote:

There was a delectable story told about them at the time of the Gandhi-Irwin Truce, illustrating their simple faith.  In the conference with the Political authorities their 'terms of peace' were stated to be release of:

            (i) Badshah Khan (Abdul Ghaffar Khan)
            (ii) Malang Baba (Naked Fakir, i.e., Gandhiji), and
            (iii) Inquilab (Revolution)....(Inquilab Zindabad — Long Live the Revolution —being a universal, popular slogan those days, they equated it with some patriotic individual whom the British Government had imprisoned! )

Pyarelal was much closer to these events, but still, this is written in 1950.  Is there anything closer to contemporary?  Further search leads one to "The White Sahibs in India", by Reginald Reynolds (1937).  Reynolds writes:

Mr. Brailsford has written of the "virtual unanimity" of the Indian people in the Civil Disobedience campaign of 1930-31..........

Mr. Brailsford also refers to the omnipresence of Gandhi's photograph (though frequently made illegal).  He found it even "in the wattled hut of an aboriginal tribesman, so poor that he owned nothing else, save his tools and his earthen pots".  Mr. Verrier Elwin, who had long sought for a man who had never heard of Gandhi, found one eventually who proved to have been stone deaf for twenty years.[43]   The present author's experiences in 1930 were similar, and Mr. Horace Alexander, returning to India after two and a half years, was startled at the change.  "Nationalism," he said, "is manifest everywhere."

The endnote [43] reads:

Lessons from the Jungle, p. 132.  Mr. Elwin did, however, eventually find some aboriginals who thought that Gandhi was something to eat.  In an unpublished letter he has recorded an encounter with an Afridi on the frontier.   This man knew of Gandhi, whom he called the Malang (Saint) but thought there was also another great leader in India called Inquilab (Revolution!).

Verrier Elwin was certainly in a position to narrate this story to Gandhi and his entourage.  Had he found the Inquilab misapprehension to be common among Afridis, he would have certainly noted it.  My current guess is that Verrier Elwin lies at the root of the story, which has been embroidered with the telling.  Of course, one could perhaps find official British reports which talk of the Afridis' demands, but those are, at present, beyond my reach.