Well so far I've used: spray and braid, quic braid, ponytail mane stay-braid spray, extra strength dep, extra strength dep mixed with jello (a weird suggestion but tried it anyway), super strength aqua net, and Shaper hairspray. None of them work. I also have tried not using a hood, using a sleasy hood, rubber bands, sewingin with thread, sewing in with yarn, sewing in with felting yarn and then wetting...sigh.
And on Cin, it's not just little irritating fly aways, I can cope with that, this is a solid line of troll fuzz about half an inch long that just never goes away. Sort of like his coat is growing straight upward on that part of the neck and then fuzzing up.