Quote Originally Posted by Slats
9. 'focustarget' is not availible to your party members if you are CC'd. Even if you have something targetted, they cannot cast as if you do. However they can happily make use of focustarget if you are dead.
I've seen this, and it can be fixed by detargeting then re-targeting the mob you are looking at. Once you re-target, the mob will show up on all of your followers' screens. It happens quite a bit in PvE.