Well, they sure are girls, and they sure are pretty, and those little ingrates should thank you for such a nice run that looks really secure and seems to have a pleasant spot!
It could be the dogs I suppose, and good riddence to the nasty one, but really, my hens seem to get real accustomed to whatever is around them once they realize they're safe. Mine even seem to taunt whatever danger threatens but can't reach, then march in to lay an egg!
I think your EEs are just slow to mature. It sure sounds like you give them a great diet. (though I'm not a fan of the Dumor brand
TSC carries, still it's a reputable feed that many do like!)
I'd say keep doing what your doing. My EEs were slow to lay, but I get some pinkish tan eggs and one that lays a very pale bluish white egg, and another pullet started laying a small pinkish egg last week, first one (hatched first week of April), but hasn't layed one since! So keep your chin up!
//edit// keep in mind, the late bloomers also seem to lay longer once they do start if that's any help.