One thing that helps, make a macro as:
/target <f>
/beckon

Then assign that macro to a hotbar.
Now, when you start an escort type quest, first target the NPC you are to /beckon, right click their target bar, and choose Focus.
This will mark that NPC as the target of your focus.
Then, when you need to use the beckon emote function, just tap your hotbar'd macro.
That way, no matter what you are doing, even while fighting off attackers, it will automatically switch to the NPC and /beckon them.