Well with a quick glance from the side the vent appears to be pointy and points straight down. I'll attempt to pull it out to get a good vent shot this weekend to confirm the sex.
Well I vented the Argentea and believe the fish to be female. I am not 100% though. The vent was hard to see as it was somewhat recessed, but did appear to have that classic U shape. Compared to my obvious males this fish definitely looks female.
I'm not sure how far from Mukilteo you are, but maybe you can come check her out sometime.