Which of the following was NOT a reason for the failure of the San Francisco de los Tejas mission?

But in three years the relationship between the Spanish and the Nabedache had soured. The Indians blamed the priests for bringing sickness to their tribe and became hostile. The Spanish were forced to return to Spain and burned the mission as they left

Primary sources are usually  more accurate and are written by someone who experienced it or witnessed it. secondary sources are those who heard of it after the fact that can lose details and or twist the event in a light that benefits them.