Not sure! I know that some sequencing has been done in other genes, like blue, that determined it was the same mutation in chickens as in ducks and I believe turkeys as well, but, silky ducks being so rare, I doubt their silkied gene has been looked into in that capacity. It is a recessive gene like in chickens and does the same thing, causes the microscopic hooks that hold feathers together not to develop, so it's likely to be at least a similar mutation.
I personally haven't found any of my birds to be higher maintenance just because of their silkied feathering, with the only exception being that their feathering does not shed water so they end up getting soaked a lot easier than the smooth-feathered individuals. Cochin bantams in general are undeniably a bit high maintenance as compared to standard utility breeds, however, if only because they demand it.
Ooh, I wasn't aware that they laid blue eggs! I really did not enjoy keeping ducks, I just have the one left and once she's gone I don't really want any more. But silky ducks are the one kind that could tempt me back into them.

I have heard that they're rather difficult to hatch and have special needs when it comes to how swimming water is provided to them, though.