Thanks for all your help so far. So then should I give her the chicks in the day time so I can see how she reacts? Do I just put them under her like I would at night?Only way to know is to try and watch how she handles them. Sometimes the broody will just ignore the chick, other times she will peck it to death. But many times she will contentedly take any chick under a day old as her own because she has a natural mother instinct.
EE are very broody bunch usually so it just depends on her temperament how she will handle the situation. My EE Smokey readily took in eggs, and she tried to take in Topsy's baby who managed to slip around the landscape fabric wall on her 5th day. But the baby knew she belonged to Topsy at that point and kept chirping for help.
Personally I would try to get the eggs from your friend on day 16 or at lockdown and move them along with the other two under her to finish hatching. Then when she's done hatching those chicks pull all remaining eggs on day 25 and candle to determine viability.
If you have a yogurt maker, some have used those to do the actual hatching phase. Others have used other makeshift ways to help keep eggs warm and hatch them without a bator.
Hope it works out, using a broody to raise and integrate the chicks is so much easier.