Presumably this was the outboard wing stalling because the aileron was high.
Sounds odd; if the ailerons were deployed upwards that would tend to UNLOAD the outboard wing, which would tend to reduce the likelihood of an outboard stall. Unless the wing was very flexible and the ailerons were twisting the outboard panel so as to reduce the effective washout, but I don't recall the 1-11 wing as looking like one that should be susceptible to that (high AR, thin)