I just picked up a six line, and i think if it wne t after the cleaner shrimps, they'd eat him!! No worry at all, IMO.
Now, if the pinky yellow fish would stop chasing the six line...
Also, while it's nice to have everyone's support for keeping my tank, I haven't actually decided to keep it. I just can't sell corals right now with these worms. I may still downsize, or go dry for a while. I'm going through my tank and any coral with eggs on it is getting destroyed. The worms themselves seem easily killed with FW dips, but the eggs are not affected by this. I have to figure out the next step.