NAV AOA DISCREPANCY
A 'xxx DISCREPANCY' message is used if one display deviates from the other display.
e.g. NAV ATT DISCREPANCY or NAV IAS DISCREPANCY.
Latest standard A330 do have a NAV AOA DISAGREE msg but only if ALL AOA disagrees or
(after EFCS rejection of one) the - Cz estimation - on the other 2 deviates.
Don't know if this also applies to A320 and what 'Cz' estimation here exactly means.
But in this case displays were in agreement as was the value of AOA1 and AOA2 hence messages would not have triggered.