I have some young syns/mels... Started out with a group of five and am down to two which I believe to be male and female. The three that I got rid of showed no blue eyes until I moved them into a smaller holding tank where they were the lone fish. All three took on male characteristics almost over night. From my experience, the blue eye theory holds true, however it often comes with maturity/dominance. The male I have right now, which is in a 220gal with other larger and more dominant fish, does not show blue eyes, yet was the largest and most dominant of the group by far. Yours look to be quite a bit larger than mine, and I would agree with the majority that they do look female. However, as others have said, I'd give them more time and perhaps one will turn out to be male.
Worth noting, to add to the confusion, I have two very mature pearsei (6 years old) and while not "vieja" both male and female display very vivid blue eyes the majority of the time. Eye color can and will change with not only age and dominance, but also mood.
