I just wanted to note for others reading this thread that these 'Dark Knights' are the Ming Dynasty which have Chinese troop skins, not some out of place fantasy Dark Knight skin. Their invasion can also be turned off, delayed, random or made to appear immediately which is handy to have a look at them if you so wish, like I did.
I thought I'd mention this as I have just discovered this mod and almost dismissed it when I saw this thread title indicating these fantasy knights were in it. I figure now they were initially acting as a place holder for the actual Ming troops but have already been replaced since the OP posted this thread.
The mod looks absolutely fantastic by the way. It gave me the same sense of awe like back in the day when the Brytenwalda mod came out. Good stuff, I look forward to getting stuck in.