Tried duco cement, it failed
super glue gel worked.
It was a rather rubber-like string bridge, glued onto wood. so it's strange that the duco didn't work, unless it was some sort of soft flexible plastic. Maybe I just didn't wait long enough (over an hour). But the super glue gel made a very strong bond, very quickly
Leather was authentic on Korean bows. Maybe crimean tatar. And in manchuarchery.org it says that the tsagaan khad bow had leather string bridges. I guess antler was more authentic on Manchu bows