Welcome to BYC. I just got my WH this summer. I have 3 girls.
On UTube their are some videos that have girls and boys recorded so you can hear the difference. It looks like you have one gold and one silver.
Congrats. Love your green grass, it must be summer.
Males will quack too, but it's just not super loud like the females. To me it looks like you have a pair the more white one being the female. There is no mistake in that one. The other one looks like a boy to me. The boy I had looked a lot like your other one. I'm not an expert on the breed though. My boy had an injury and had to be put down, so I never saw him grow completely out past 3.5 months.