great closeups! and yeah, flash can distort colors.
in the first photo, lindy looks like a girl because i see white rings around her nostrils. you're the best judge of that though.
and in the second photo, lindy's cere seems a bit bluish. (which also implies she's a girl, btw.)
and like everyone else said already, i think sky's a boy.
When budgies are a younger age (6 week to 6 months) it is much harder to work out the sex and it takes a trained eye to pick up the slight differences. The things to look for are an even pinky/purple colour over the whole cere for young males and a pink or blue cere with noticable white rings around the nostrils for females. This is where many go wrong for we associate pink for girls and blue for boys and many pet shop employees believe that this is how to tell the difference and incorrectly sex the birds.