It’s difficult to know exactly how dolphins helped Nikki to speak.
It’s obvious he felt very excited swimming with them and he should have sensed a strong connection with the dolphins, this kind of situations can trigger strong reactions in people who are in special situations.
Healing abilities of dolphins aren’t an media invention, nor those of other animals, like horses, which also can help people with behavior problems.
To raise £10,500 has to be difficult, you have to save for a while and deprived of many things.