He says he "tricked" the kid into playing with him and the kid doesn't like him.
"Tricked" here may be a child's way of expressing that he adapted to a different (well, slightly different) persona in order to bridge social gaps with another person.
The underlying issue is why this feels like being "fake" to him. Some people are definitely just made to feel that way, but you're right to be concerned about it. It certainly doesn't make for a happy or fulfilled life, that outlook.
It's also possible that his assessment of "trickery" could be an early expression of imposter syndrome. If he's highly perfectionistic, that might be what is going on with his rigidity, too.
