Nitrogen triodide energetics
I'm not sure what your question is. The reaction from NI3 is largely exothermic (Wikipedia gives –290 kJ/mol as the reaction enthalpy), which is consistent with its explosiveness. The reaction from NI3 · NH3 is also exothermic: you quote the heat of formation of the NI3 · NH3 as being +146 kJ/mol, and the heat of formation of product NH4I is –202 kJ/mol. Both are largely favored entropically because they release gas.