No expert on details of feather structure, but Swainson's does not have an emarginated P6. (Outer primary is P9, P10 is reduced, so P9 looks emarginated as does P8, P7 and P6. So that eliminates Swainson's if I am seeing the structure correctly. Also spectacles on Swainson's connects with eye ring, your close up shows a dark area between eye and the stripe? Fun bird and just an opinion, I am sure a bander would know if that P6 is emarginated or not.. if you know one.
