I'm currently on my Tablet, which is why I can't read Warcraftlogs very well. But there are two things I instantly recognize: you do almost zero AE damage while your colleague does some millions. Second thing is that he manages to get out several additional shadowburns. There is definitely room for you to improve.
Imho the thing that separates mediocre from good wls is clever usage of shadowburn and havoc. That said: you casted more havocs than he did. If you used them well, that already was a good thing!
Maybe I'll find some more facts when returning to my PC later.