Maybe you could have a pair of vanes. Each vane is physically limited to a portion of possible angles. Vane A would only work above say -10 degrees AOA and va

Maybe you could have a pair of vanes. Each vane is physically limited to a portion of possible angles. Vane A would only work above say -10 degrees AOA and vane B below +10 degrees AOA. This would give you a regular test of both sensors when the AoA changes in normal flight. You have more bounding of correct values.