I’m not too sure about this take. There is also another one:

The shared history of oil and nuclear energy - The Maastricht University History Department Blog

The oil company Mobil in particular invested heavily in the development of this technique during the 1960s. Therefore, when Mobil got into uranium mining in 1968, their engineers got quickly ahead of the traditional mining companies in furthering the development of the leaching technique in the uranium sector. In the ten years following the entry of Mobil in the uranium (…)

A 1976 Federal Trade Commission report found that twelve of the top 25 uranium mining and milling companies in the United States that controlled 95% of all US uranium reserves were partly owned by oil firms.