A rollaway nest would be a problem. Another potential problem is that you want the chicks to be as young as possible when you try. A hen cannot count days but some people think it helps if the hen has been broody for a while before you give her chicks. That may be a factor for some hens but I don't think it is for others. I've had broody hens that just went broody take chicks away from the hen that hatched them.
I regularly give chicks from the incubator to a broody by sticking them under her at night, then go out the next morning at daylight and check to see how it is going. You can't do that with that rollaway nest unless you can securely block that rollaway part so the chicks cannot get trapped away from the hen. If you can block that rollaway ramp so chicks cannot possibly get past it you can try sticking them under her after dark.
I have given a hen chicks in the daytime a couple of times by showing them to her and putting them down near her. She called to them and took them so it works sometimes. But there is a chance she will ignore them or peck them to drive them away. Again, I'd be nervous about that rollaway nest.
You could build a pen with a nest and maybe water and food and move that hen there after dark. After she settles put the chicks under her, then be there at first light to see how it is going. I don't feel real good about this but it could work.
I see two potential problems. She may not accept them no matter how you do it. And if you don't get the chicks under her soon they may imprint on you or something else and not the broody hen.
I'd love to hear what you try and how it works. Good luck!
