Most games tend to look at anything that has rankings and leaderboards the most, so I would definitely recommend not using this for PVP. I would also say that special events are also risky.
At the end of the day though, if an admin or dev looks at your account and detects cheating at any aspect of the game they're going to ban you, even if it might not be permanent. You're just as liable to be banned for cheating in single player as you are for multiplayer, it's just a matter of what the admins and devs prioritize.