I’m so sorry to hear, some hens are just not made to be mothers, remember not to beat yourself up about it, it’s not something we really can control, great idea with the incubator:hugs
Oh I’m so sorry for your losses, if this chick should have a chance I would put her under a heat lamp or on your, I have heated up chicken by laying them by my neck and blowing on them but if you have a heating lamp use that.
I would also dap some sugar water on its beak and just letting it...