It very well could. Any high fibro bird is going to be really inbred. I know Ayam Cemanis seem to deal with a lot of immune issues, having spoken to people who own them. But I’m not sure about sumatras. I think they’d be an interesting bird to compare against and see if it’s just a cemani and silkie thing or something else.
Also it looks like the second study isn’t silkies but another Chinese breed.
That's why I said I don't know about the other breed. Silkies definitely don't have the best breeding, but since the second study was done on another breed there's definitely some correlation between the fibro gene and the problems you listed