When I first started embroidering, I took a few classes and one of the sprays we were using in class could only be removed by ironing. Place a Teflon sheet over it, of course. I would try ironing in a small area.
Wonder why. I use spray adhesive all the time and it always washes out. I also think that less is more when spraying.
Hope you get it removed! Temporary often just means that it is temporarily re-positional! I, too, would try as laffma1 has suggested. I have several goo removers in my cabinet... wish that I could share them for you to try. All the best, Joan
Don't know what country you are in, but if you can find a product called "goof off" made by WM Barr & Co. (www.goof-off.com), it should work. I used it on, of all things, a dupioni silk project, and it worked great. Good luck.
Have you tried contacting the manufacturer of the spray?
Hopefully washing has not set the adhesive permanently so it can still be removed.
If washing didn't remove it doesn't sound like it is temporary spray.
Many "temporary: glues are not.
maybe try acetone if it is colorfast? I'm not sure..