They built a fort not far from the city of Tumbes, Equador. There isn't any mention of them coming to harm --which would have been noteworthy if it happened before De Soto's clash with the army under General Quizquiz, as the Spaniards faced no organized and effective resistance until that skirmish-- but there are records of several waves of reinforcements joining Pizarro and his men at Cajamarca and Cuzco, in addition to other expeditions into modern Ecuador. It can be safely assumed that the men left behind either garrisoned the small fort on the coast as a beachhead for further conquistadors or joined one of the arriving expeditions as their health and enthusiasm allowed.

Source: W.H. Prescott's History of the Conquest of Peru.