Question: Incorrect Solution from fsolve

I have a rather complex expression that I want to find the zero for as a function of two other parameters, i.e. I have a function

Denom := (s,M,g) -> stuff

that I want to find the zero of for a variety of values of M and g. In some cases the solution will be complex, which is entirely acceptable. However, the real part of the solution should never be negative, and yet that is the kind of result I am getting.

As an example (illustrated in the worksheet, when attempting to find the zero for M = 3 and g = 0.2, fsolve gives me s = -6.1 -1.4i. However, when I plot the function with the parameters input already, I can clearly see a zero at s = 9 with no imaginary component. Why won't fsolve find this zero? How can I make it do so?

See the bottom of the attached worksheet for the main problem.

 pole-dragging-mapleprimes.mw

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