I would say no, you won't get a gold related RWT ban.
Depending on your I.P, and the activities that your account has been involved in after those 3 months you might still be hit by a RWT ban if you deal with account sales/training etc.
I'm not sure where I heard this information, nor am I able to verify it, but I remember reading somewhere that Jagex hold's trade logs for ~2months.
GL!