Although they have never been observed, theoretically gluons can exist outside of the nucleus of an atom in the form of a "glue ball". Since the predominant mechanism of Higgs creation at the LHC was observed to be a gluon-gluon interaction (with various virtual particles playing out in the conversion), what are the chances that a "glue ball" as predicted by QCD is the same animal from the particle zoo as a Higgs boson?
They can't be the same thing. As Wikipedia says, it's possible to calculate certain properties of glueballs from QCD, including their masses, and the masses don't come close to what we've observed for the Higgs boson. Also, the Higgs doesn't have color charge, so it doesn't interact with gluons, whereas a glueball would. That would make a large difference in the cross section of any strong interaction, and we don't detect that.