The Hidden Forest

Trying to accomplish Achievements on my chanter alt Abin, but some of them won't register. Case in point Froggy, Trak, Naggy and King T. I know Abin was in on those kills because he completed Headhunter. I know also that the Achievement does not need the toon to get hits on the mob because my other boxes never get in fights. They just sit at the zone in and mooch and get the Achievement.

Thanks.

Sometimes achievement won't register. I remember killing Queen in Crystal few times and still, didn't register (yet I have completed WB hunter too).
All I can tell you is to keep killing, but I would tell you to make sure your toon hits and is on aggro list of the mob. Don't use swarm pets or pets, light a candle and pray
Don't think there are any other solution than perseverance on this.