Solo'd this quest as a 72 druid. Strategy:
1. Put your hand on the keyboard (left or right is fine. I use the left hand -- the one that makes an L-shape if you hold it up in front of you with your thumb and index finger extended)
2. Press a button. If it takes your character farther away from Mage-Lieutenant Malister, try another button
2a. Keep pressing that button until you're standing less than a foot away from Mage-Lieutenant Malister. You may need to repeat step 2 until you get close enough to him.
3. Put one of your hands on the mouse (could be the same one used for step 1-2a. I prefer the right hand)
4. TRICKY PART: Like in step 2, move the mouse in one direction. If that direction puts your mouse cursor (the hand on the screen with a silver glove on) farther away from Mage-Lieutenant Malister, try another direction. This may take a while, since there is an infinite amount of directions you can go. Don't give up!
4a. Keep moving the mouse in the same direction until your mouse cursor turns into a question mark (looks like this -- ?) on top of Mage-Lieutenant Malister.
5. Press the RIGHT mouse button. This is right -->, this is left <--. Be sure to press the RIGHT button.
6. Repeat step 4, except move the cursor to the button labeled "Complete Quest". When you have it in the right position, the button will light up! Then, press the LEFT mouse button (see step 5 for a handy guide for mouse buttons)
You did it! Congratulations!