I have an orphaned Mandarin duckling that's currently in the brooder with a mama silkie and silkie chicks the same age. They're all 2 days old. The chicks are eating but duckling seems uninterested in food (all flock starter crumbles, what I fed babies last year but they were with mothers always...
If you can gently warm it up and it seems lively again, you can probably tuck it back under mama if she's settled in for the night. They do get very sluggish when cold. I hope it perks back up.
Almost every time I've jumped in to help one hatch, I've wished afterwards that I had left it alone (had a few that failed to thrive in a big batch and had no way to know if those were the ones I helped...) I always resolve to let nature do its thing but it's sooo hard! Hang in there :)
One of my silkies has claimed several of the standard hens as his girls... Having at least a few ladies for each fella might help, if you aren't set on keeping them separated by breed. At least with my standard hens I think they prefer the smaller males to the bigger, rougher roos we had before.
Silkie roos in my experience are more tolerant of each other than most breeds. I currently have three silkie roos, two are brothers and the third is unrelated. They get along fine, no sparring that I've seen, and they all range and roost together. Each has a few hens that follow him around, his...
Two of my silkies got broody together this spring. They hatched a few babies themselves and I gave them a dozen or so more from the incubator (including a call duckling). They are both first time mamas but they are so good at it. I love silkies.