Not really. Pentaquarks are a prediction of the Standard Model (SM), but nicely they are a true prediction. The standard model was constructed to contain mesons

Not really. Pentaquarks are a prediction of the Standard Model (SM), but nicely they are a true prediction. The standard model was constructed to contain mesons (2 quarks) and hadrons (3 quarks), so the discovery of tetra and pentaquarks is a rather stringent test for predictions of the SM. It may be, that new effects are more important for pentaquarks than for regular hadrons, since they are less well understood. Someone who works on alternate theories of the strong force can just look up all the precision measurement of the proton. If the new theory does not work there, then he will start another project. So a new particle is a rather interesting test. This is of course also true for the SM, but at the moment it looks like another brilliant confirmation.