Neat Possible Discovery: A 4-neutron state

In Japan, there is evidence for a 'tetraneutron' state, where a ball of four neutrons, with no protons, was part of the products from the high-energy collision of helium-8 with helium-4. Check out this article, which also has a link to the published paper on this finding. There will need to be verification of the discovery, but if true, theorists are not entirely sure how this state arises - it has not been predicted through quantum chromodynamics (QCD), which is the theory of the strong nuclear force. This is not a true atom, since without a positive charge there are no possible electron orbitals, but it is an interesting object with some possible new physics if real. Is there a different 'interneutron force' that we do not understand? Can this be rectified within the present QCD?