I don't understand what you mean by this? Are you saying that your slave isn't targeting anything but still casting? If so, that should be the case. If I'm not mistaken, that was one of the draws of using focus-based casting in PvP...so the enemy couldn't see who the slaves were targeting because they didn't physically target anyone.
You should be able to simply add an assist in there to get them to actually display a target. It should have no impact on anything other than display since you're spells all cast @focustarget
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