Solution 1:

A Gnome Shell theme changes shell buttons, colors, panels, etc., and not the actual terminal I believe.

For example: Draculatheme.com has a GTK theme as well as a gnome-terminal

I believe you would need to find out if that theme has a terminal "theme"( for lack of a better word) and set it to that.

I was trying to find a gnome-terminal version that matches the theme but im not able to.

Someone that knows this MUCH more than I do might be able to confirm/deny anything I have said and inform us correctly though.