I have one minor correction to make as I just noticed you said "folder" in your original post. In NC, it is legal to conceal folders. My answer was about sheath knives.
That said, the knife you want is no folder. It's a switchblade and therefore is not legal to be concealed, so my original statement still applies.
Looking at that holster, I would call that concealed. It's just a rectangle with no really way to tell what's in it. Now if you had a molded kydex sheath that only covered the lower half and a person could tell it was a knife, that might pass.