Very little sticks to silnylon, other than another siliconized item. That is why sealers that work on silnylon are thinned silicone adhesive of some sort.

I used Kent's staple trick when I was making costumes for community theater. I had people put on clothes to be altered and custom-fit them with staples instead of pins. They stayed in better until I got the clothes home to stitch thme properly and it was a quick solution. I pulled the staples out as I sewed. I haven't tried it with silnylon, but it should be fine to staple INSIDE the seam allowance.

CM