Just wanted to serve the poor?
Could it have been that the "straw that broke the camel's back" was that Judas really just wanted to serve the poor? That he was drawn in by Jesus' call to serve the marginalized but got turned off by all the "I am" talk? Maybe he misunderstood what Jesus' meant by the "Kingdom of God" as just an earthly kingdom . . . not something much larger ruled by the "Son of God".