If you collect on a daily or even every few days basis,, you have no worry about that. Heck, the only chance of that will be if you have one of them go broody, and actually sit on them for at least a week. THe breeds you are mentioning tend not to be of the broody type, so even if you did have a roo, not to worry. Perhaps one of the barred rocks, but even that is unusual if they are hatchery birds. I ordered 10 female chicks last summer from Meyer hatchery and felt the same way you did. Of course, they guarentee only a 90% sexing rate, and low and behold, one of them turned out to be a roo. I was SO UPSET at first, but decided to inch along and see how it went instead of my first instinct to give him to a breeder in town. He has turned out to be a wonderful protector of my girls, I free range them since they have him to protect and give watch. From your pics you seem to be in heavy predetor area. He also breaks up any sillyness that goes on in the hen house. I have heard that a good Roo is worth their weight, and at 5 months along, he is showing promising signs.
Keep us posted! Oh, remember when chickens are moved to a new area, the laying can slow down for a week or two while they get adjusted, so don't be disheartened if you don't see eggs for a bit.
Good Luck!
MB