What good is a theory that doesn't conform to experimental results? That's a rhetorical question, by the way.
Was Newtonian mechanics wrong when it failed to correctly predict the orbit of Uranus and they had to make up that Neptune planet to conform to experiment?
The introduction of a new particle as a consequence of your theory and experimental results is by definition a prediction from your theory. The merits of it depend solely on whether the prediction was actually true. Neptune exists? Score for Newton. Planet X doesn't exist under Mercury? Newton loses.
Same with the Higgs. If the Higgs exists, it is a valid prediction that adds additional confirmation for the validity of the Standard model, if the Higgs doesn't exist then I'm sorry Standard model, it was nice having you.