A Storm-Petrel Photographed

Venicio Wilson forwards this photo of a Storm-Petrel photographed by Christian Gernez on the Lindblad Expeditions/National Geographic's Sea Voyager, apparently near Punta Mala, apparently a few days ago. Additional photos are apparently on their way, but in the meantime let's start speculating, shall we?
We would strongly lean for Wedge-rumped Storm-Petrel, probably the commonest Oceanodroma in Panama waters, and not just because we like erring on the side of caution: there's just a lot of white on this rump, and the rump is shaped like a wedge! Also, if you squint you can almost imagine the white extending down the sides, a tell-tale tail. Shape and lenght of the tail itself is not particularly clear, but again if you squint you can almost see it as slightly notched, but not deeply forked.
¿Any dissenting opinions?