Were the Dene people unaware they had mined ore for the atomic bombing of Hiroshima and Nagasaki until the 1990s?

Question

From a web project called The Forbidden Rock Prophecy (elsewhere it claims the atomic bombs were prophesied):

Nor did they know what the materials they carried would be used for. So in addition to the physical and environmental consequences of uranium mining and transportation there were mental and spiritual consequences as well. The Dene did not learn that the uranium mined from their land and carried by their men was dropped on Hiroshima until approximately 1990.

Likewise, from a blog post titled The Hibakusha who Apologized for Hiroshima and Nagasaki

Until the 1990s, because of their isolation and neglect by the Canadian government, they had little understanding of where those “money rocks” had gone, and little awareness of the rocks’ connection to numerous deaths among them from strange new illnesses. But then journalists, academics and filmmakers began to appear with questions about the past and information about the causes of those illnesses. The Dene were dismayed by the neglect they had suffered, but were equally burdened by the new awareness of what they had helped to bring upon Japanese people. Their sense of responsibility knew nothing of the civilized impulse toward self-exculpation. They felt responsible for not having asked questions about what they had agreed to work on, for not having made every effort to understand the implications of their participation. That’s an ethical standard that few people could live up to.

I'm not skeptical of the mining of ore being secret during the war, or that they worked in unsafe conditions. However, I'm skeptical that an indigenous people who had contact with westerners took half a century to be aware of a connection between what they did and one of the most well-known incidents in World War II. (I'm also skeptical that cancer wasn't previously known about by indigenous people, but that's a separate question)

Were the Dene people unaware they had mined ore for the atomic bombing of Hiroshima and Nagasaki until the 1990s?

Answer 1

The 1988 book The Social Dynamics of Peace and Conflict: Culture in International Security

Georges Erasmus, former President of the Dene Nation, pointed out, "We're aware that the uranium for the atomic bomb that was dropped on Hiroshima and Nagasaki in 1945 came from Denendeh"

citing to Akwesasne Notes 16(6):4 which was published in 1984.

See also the 1976 Canadian House of Commons Debates, Official Report, Volume 12:

Its source can be traced to the ominous smoke which rose over Hiroshima and Nagasaki in August, 1945. It is now generally accepted that material for these first atomic bombs came from the Eldorado Mine at Great Bear Lake in the Northwest Territories.

And the 1949 The English-speaking peoples: a modern history

The Canadian government took steps to assure the supply of essential raw material by expropriating the uranium deposits at Great Bear Lake, and work was carried on at a pilot plant and a special laboratory on Canadian soil. The fruits of these extensive efforts were revealed with terrible impressiveness in August 1945 when two atomic bombs dropped on Hiroshima and Nagasaki sealed the defeat of Japan and ushered in a new era in human history.

And in the 1946 article "The Eldorado Enterprise" The Transactions of the Canadian Institute of Mining and Metallurgy and the Mining Society of Nova Scotia, Volume 49

In the excitement over the dramatic revelations following the destruction of Hiroshima, the vital position of Eldorado in the uranium project and the contribution of the Company's organizers and technical staff have been largely overlooked.

The discovery of pitchblende at Great Bear lake in 1930 began an important series of events. Pitchblende, then important chiefly as a source of radium, was known to occur in significant amounts at only one other locality in the world. The full consequences of this discovery to Canada and the United Nations could not then be foreseen even though the immediate importance of a commercial source of radium was recognized.

...

By 1943, production was at the normal rate and regular shipments have been assured. Difficulties at the refinery were in prospect due to the changing emphasis on the production of U3O8 and the necessity of meeting exacting time schedules. Under the direction of A. H. Ross, the batch process — long in use — was converted to one of continuous extraction. The quality of the uranium produced was improved to the required standard, so that Eldorado was well able to make its contribution to the uranium project.

So the leader of the Dene people definitely knew by 1984, and this was public knowledge much earlier.