Instances are 99% safe...
Im following that thread afk botting in brother island, and guys, there are multiple instances to chose from, so what if they don't respawn? make your macro request a new instance after 6 hours of killing in it... invest some time in making your macros idiot proof, and by that I mean, safe from idiots who don't know how to mind their own buisness...
U can actually add functionality to send u a text if someone snoops around or send u a tell if you REALLY have to afk in open zones...
BUT is it worth getting banned over? Get some peace of mind and just make your toons request an instance with lots of mobs in it, kill there for 6 hours then reget the mission, thulisaur island has a good one given by #praetoria with mobs enough for hours of killing, and that just one example... you can rotate the Dead hills missions, or any other instanced mission, just have to take the time to get it setup, but I promise you that when you do, you will sleep better at night.
I have botted for YEARS without ever getting suspended or banned..., my bots answer tells, camp checks, send me text messages and I can monitor them from my phone, I have come back to my computer on a few occasions and seen my bot have had conversations with other players and a GM one time even, they all where satisfied with the bots answers and went on their way...