Sean Kingston NEVER Dimed Out The Game to Cops

The Game is flat out wrong when he calls Sean Kingston a dirty snitch ... this according to Sean's lawyer, who swears her client never spoke to cops.

This whole beef started when Sean got his $300k chain snatched at an L.A. club -- Game insists Sean told cops he was involved, but attorney Michelle Iarusso tells TMZ that's not how it went down.

"At no time did my client bring up The Game during the investigation. In fact, [Sean], to date, has not even spoken to any member of the LAPD regarding this incident." TMZ obtained a copy of the police report ... and Game isn't mentioned.

Iarusso is repping Sean in the lawsuit he filed against the club, but says that case is purely about the club's alleged negligence.