I think that dolphins helped Nikki to speak because he liked them very much and he was afraid when he thought that he wasn’t allowed to swim with them.
I really think the dolphins helped him because they were a wonderful stimulus. Nikki really loved dolphins. The fear to not swim with the dolphins conditioned him to speak.
There’s a lot of other stories about the therapeutic effect of animals, like the stories about horses which help children with a psycological diseases.
I think Nikki’s mother raised the £10,500 going to a TV program to ask people for help. I would rise this amount of money doing exactly the same as her.