The dimethylammonium metal formates (metal = Mn, Fe, Co, Ni) are metal-organic perovskite analogues of interest for potential multiferroicity. In these materials, electric ordering arises from the organic A-site cation ordering via hydrogen bonding to the metal-formate framework, while magnetic ordering arises from the B-site cations. We have observed a magnetic excitation below 1 meV in the magnetically ordered state of the Mn material using MERLIN, and propose here to take advantage of the cold neutrons available on LET to investigate this excitation systematically across this family of materials. Our results will help to elucidate the magnetic structure of these materials, including the surprising complex superexchange across the formate ion.