I'm not sure what's he's looking for. Perhaps he simply wants you to start with the definition of a complex curvilinear integral instead of directly making a substitution, in which case it'd start like this
But I didn't do much here... do you want help for the actual computation? Also, I think there's a tiny error in your red rectangle, it should read (z^2+1/z^2-2), and not (z^2+1/z^2-2)^2 (even though you corrected it later and the calculation looks correct I guess)