I'm not sure why the article presented by the op says that making this dish is so difficult. It's possible that he tried to "stuff" the roulladin after dipping in egg wash. The egg wash would effectively prevent the chicken meat from sticking to itself.
I haven't tried making this particular dish with bacon and american cheese. But I have made both Chicken Kiev, and Chicken Cordon Bleau at home. With both, I simply pounded the chicken breast into a thin, uniform piece of meat between two sheets of plastic wrap. I then placed the filling onto the middle of the cutlet and folded the meat over the filling, like a burrito. I then allowed the chicken to sit of 5 minutes, to allow the moisture to evaporate a bit. Finally, I dredged in egg-wash, seasoned flour, egg wash again, and finally, bread crumbs. Then, just fry in a couple inches of hot oil until the breadcrumbs start to brown. Carefully place onto a cookie sheet, and bake at 350 for 20 minutes. They came out juicy and perfect.
If the bacon was pre-cooked, and crumbled, or at least broken into pieces that would fit into the rouladen, and the cheese place over the bacon, the same method would work. The bacon and cheese aren't meant to stick to the raw chicken. Rather, the chicken sticks to itself, if not too wet. Of course it has to be handled with great delicacy as the bond isn't that strong until the cooking takes place.
As for the KFC secret recipe that is given in the article, it is fairly similar to recipes that were tried and submitted a few months back by DC members. We got fairly close with some of them. So it should taste pretty good. But making the "sandwich" should just be a matter of careful technique.
Seeeeeeya; Goodweed of the North