I very much doubt that 6 units of three band parametrics were part of Dimebag's signal chain from fingers to amp speaker when he laid down the tracks -- but I would be willing to accept that everything else, from stomps to amp speakers, in the current version of Amplitube is as close "real" as one can get to what he had, using today's technology -- the memories of Dimebag's guitar tech -- and some "reverse engineering" by knowledgeable folks.
Six units of parametric EQ are very likely there to approximate the mixed (and mastered) signal -- which Amplitube could not hope to model for "real", no matter how great the attention to detail.