The recipe is here:
Kerri says, ".. I didn't make the noodles right, they weren't very good. Not chewy or bouncy, but soggy on the outside and sort of stiff in the very middle..."
The jjajangmyeon noodles should be cooked thoroughly and the texture of the noodles are supposed to be a little
chewy. Just in case, did you put a lot of water in the pot to boil the noodles? If the amount of boiling water is not enough, the noodles will turn out like the ones that you described. (soggy outside and uncooked inside)
It looks great to me!