Autism isn't a disorder that can be cured, although work can be put in to help manage it. This comes from a good number of years working with autistic children ^^.
Avenger's right, in a sense, that some are able to understand "logical" systems quickly and generally have difficulty in social situations. It's a spectrum though, some may only misunderstand jokes or seem eccentric. Whilst not "100%" in social situations, many have an understanding of what society expects from them and what's acceptable or not. There's the reverse though, there are others that don't understand the implications of stealing or violence.
We really need to see this evidence if we're going to brand it as cheating. A typical autistic behaviour is collecting/organising things, so it's possible that cheating was merely the most efficient way to complete his collection. However, there are the alternatives, outside intervention or methodical gaming. At a glance, the boy seems to be the kind who takes pride in earning achievements. It's not evidence by any means though, autistic people are generally difficult to judge at first glance.