If all else fails, I have threaded a hand needle with matching thread and hand connected the threads. I put my needle in beside where the stitch should be, go through to the other side going over the bottom thread and coming back up on the other side of the top thread where I went in. I then tie a knot and run the needle through the sandwich to the next spot where the stitch should be. It takes time but it can be done and knotting the hand thread and burying the ends make it appear like normal stitching.