Thanks for the in-depth write-up. My process is a little different but the gist is you’re pre-punching holes and handstitching, if I read that correctly.
I ended up using a “jerk needle,” switching to harness needles with a saddle stitch using the same length of thread, with excellent results. The issue is always not enough room to either run the harness needle, or stitching with my Artisan. It got done.