Shea butter likes to stand alone. It will definately act crazy if you mix it with gel and other products.
I take what older people say about hair texture with a grain of salt. They were indoctrinated with the idea that straight hair was good hair. The only good hair. As early as possible, they made their kinky hair straight. For some of them, the idea that we would voluntarily allow our hair to "go back" is just appalling.
Our notion, to borrow the phrase from India Irie, "what God/dess gave me is just fine" is completely alien to many of them. As for the hair dresser, she just wants your money back in her pocket.