I'll try the wide zig-zag stitch. I'm concerned that no matter how far away I get the stitch from the edge, the satin will still act weird. I've done my straight stitch method on cotton fabric with fusible and it worked beautifully. As long as I'm not right at the edge, no fraying, no issues, perfect. It's just this dang satan... errr, satin, mistype there :D
I've definitely ironed it well, so I'm thinking I might tell them to treat it nicely and repair if needed, rather than get so annoyed with the fraying satin....