hatching pekin duck question

[snipedogie]

I have a pekin duck and a chicken sharing the same nest...all duck eggs. One duckling hatched and is doing fine. Two others are partially hatched but neither mom is sitting on them and they felt cold to the touch and seemed weak, so I brought them in and have them on a warm heating pad with a warm damp towel. Did I do the right thing or should I put them back in the nest box? Thanks!