When you say 'wanted', are you referring to a mission?
I've found that jumping back into SC, and again hitting USS's, you'll eventually end up finding him again.
However, it'll be a new instance and he'll be back to full health, and if he didn't have an escort the 1st time around, he might have one this time.
Suppose it's also possible to hit a USS, and have an NPC tell you that he left the system... I dunno, that hasn't happened to me yet.
All the above assuming you don't have a wake scanner to follow him to wherever ever he jumps.