I'm pretty sure Jagex reviews all mutes by mods and will removed them if they were undeserved.
Gambling is not against the rules (as far as I know) although Jagex has always discouraged participation and are now forbidding Pmods from taking part.
Jagex doesn't really operate on a points system anymore. It may show up on your account but I wouldn't worry about it. This would do nothing to bring you closer to a ban and I've seen accounts with tons of temporary mutes but no permanent mute.
Good luck man, I think you're fine.