After 10 days, they are plenty ready to come out. Birds usually only require 1-3 days of in-coop isolation.
Lots of factors play into laying. Age, molt, weather, nutrition, and stress are some these. Can you tell me what the temps are like your area and what you are feeding them?
Were they sold as laying or as point of lay? "Point of lay" can be anywhere from 5-7 months or so. It can either refer to a pullet who should be laying within a month or two, or a pullet who only first began to lay within the previous month or two. Laying, on the other hand, means they should already be laying. It's possible your girls are only point of lay, which means they should begin laying with another couple weeks on into a month or even two, depending on exact age. It's also possible the sellers lied to you, and the birds are older. Check to see if any of your girls are molting - losing lots of feathers or covered in pin feathers. If they are, they are at least 1 year of age, and a cease of laying during molt is normal. Extremely high temps, extremely low temps, and lots of weather fluctuations can also result in a lack of eggs, as can stress caused by new environments or nearby predators (as well as being moved to a new home - although yours should be about over that now).
They should lay in the nesting boxes. You can add ceramic or wooden eggs to encourage them to do so.