It is not clear to me if that is supposedly a story that you knew first hand, because you do not put sources and you could have invented it, but I have heard similar stories from quite some time ago.

Nowadays there is not that much of a problem, what you have to do when you share a lottery ticket is for the one who has the ticket stub to send a photo via instant messenger to all those who share the ticket, as it is considered evidence in court.

That way, Charles could go to the police or the court and report Kelvin.