Hey,
From the pictures it is rather difficult to tell what sexes they are.
If they were malnuritioned, the males may not color up completely. Nevertheless, it is usually easy to tell linked-sexes apart because of the long fins and colours of males. If your tank size allows it, order another batch of them and hope for the best. Otherwise you could also wait a few weeks if maybe one will still develop to look like a male…
Greetings Rafael