1st. If they both look like that one then I think they are both female because I have a button quail that looks identical to that one and she lays eggs a few times a week but were she lays is weird, she lays not in her nesting box but in here shavings, and then buries them so just check there shavings/ whatever you are using because there may be a few eggs also my females didn't start laying until a year.
2nd. Yes you can put in more females just keep an eye on things for the first week or 2