Thank you ladies but I'll be doing applique type towl embroidery LOIL
Just my two cents - If you actually used a FSL oval for a knockdown stitch, it's too much stitching... Your knockdown stitch pattern should not be as much as for FSL... Also, when I use a knockdown stitch on a towel, you don't need to use a WSS topper and I never use a double layer of WSS for stabilizer...the knockdown stitching will stitch and hold the loops of the towel without a WSS topper...
I think you can save the towel with mrskiki's idea of soaking the towel repeatedly to get out the wss. To keep the knap of the stitches under control, the design is going to be stiff. I haven't noted the stitched area to be uncomfortable when using it though. Keep experimenting to find what is the best method for you. And let us know what works for you. We love to see projects and learn methods that work.
Try just hooping one layer of WSS Float the towel with sticky spray on the WSS
Then place tulle on top and some wash away. Your design will not be stiff. It is easy to do. I do towels all the time this way with no problems,, Good luck.
Try soaking it in warm water with a few drips of water softener like Downey, changing the water several times as necessary. Hugs. Nan