If you do what @Miss Lydia says, I'd put a thermometer under the heat lamp and try to get temp around 99f by adjusting the distance of the heat lamp to the eggs, Maybe put a humidifier near the eggs to try to get the humidity around 60-70 % a water bowl might help raise the humidity also.
What a sweetie!
Are the other babies still under her? If you have an incubator it might be a good idea to put the ones that haven't finished zipping in there, if she attacked that duckling I'm sure she will attack the rest.