Sorry for being late to the dance!
In favor of looking at the Franciscans again, we can point to the explorations done in the early phase of their arrival (1768-97) father Garces in particular took pains to explore areas to the north of the Gila river. Also, we have it from a Catholic source about the retrieval of a cache of gold from the Franciscans' mission on the Colorado river, done by Mexicans long after the departure of the Franciscans. The Franciscan padres were not happy with the "secularization" of the mission properties which began by order of the Mexican government circa 1821. They had every reason to conceal what ever treasure(s) had been accumulated, rather than allow the government to simply seize it for their coffers. Plus they had a full year to execute the hiding of valuables and mines. Remember, the impressive mission churches and buildings at San Xavier del Bac and Tumacacori were both built by Franciscans, at least the buildings we can see, and these buildings have smelter slag built right into the mission walls. The mission at Bac was the site seen by early American travelers who remarked about the altar service of solid silver, worth an estimated $40,000 in 1840s dollars. The Franciscan padres might not have been quite so aggressive, and really were 'losing ground' insofar as the number of missions they were maintaining, but they were certainly accumulating treasures and especially silver. I would not write them off as the original owners of a treasure secreted in the Superstition mountains by any measure.
An unknown number of priests from other Orders also served in Pimeria Alta, the one credited with the very first "documented" placer gold mining at Baboquiviri for instance was an Augustinian priest, not Franciscan or Jesuit.
In favor of a LATER date for the creation of a cache/depository of treasure in the Superstitions, I know of several items recovered in the wilderness area which were clearly Mexican and dated to the 1820 period. Far too late for the Jesuits.
Arcana - it won't win over anyone to your point of view on things by calling anyone an Alpha Idiot. We don't need to call each other names to get the point across, and can disagree without being disagreeable.
Sorry for the long winded post there, got carried away! Please do continue,
Oroblanco