So this was more involved than first glance as there were several issues.
First, as far as I can tell, originally finishing blows ended with 2 exclamation points, so GamParse was looking for that. I changed it to check for both versions (!! and !) however that was not the only issue.
I was told by reliable sources that the second Finishing Blow message is an error, that it only hits one time but has two messages. GamParse was only suppressing the first message, so it was still displaying the damage for the second hit.
So, I've changed it to work thusly:
1) Finishing Blow is now it's own Damage Type, meaning it will show as "Finishing" damage instead of "Crush" or "Slash" or w/e weapon type you are using.
2) GamParse will ALWAYS suppress the second damage message, regardless of setting.
3) If the Suppress Finishing Blows option is Enabled, GamParse will suppress the first damage message as well as the second.