Im not even sure how to evaluate the result but I imagine this isn't the worst starting point. To "reduce the complexity" of the integral use:
$$ \cosh(t) = \frac{e^{t}+e^{-t}}{2} \\
\cosh^2(t) = \frac{\cosh(2t)+1}{2}$$
Together the hyperbolic cosines can be replaced with exponentials which may be easier to handle if you use appropriate contour integral black magic.
Hint
Im not even sure how to evaluate the result but I imagine this isn't the worst starting point. To "reduce the complexity" of the integral use: $$ \cosh(t) = \frac{e^{t}+e^{-t}}{2} \\ \cosh^2(t) = \frac{\cosh(2t)+1}{2}$$ Together the hyperbolic cosines can be replaced with exponentials which may be easier to handle if you use appropriate contour integral black magic.