We present a study of alloy-induced shifts of the electronic levels associated with isolated interstitial iron (Fei) and iron-aluminum pairs (FeiAl), in which iron is sitting in the first-nearest (stable configuration) or second-nearest interstitial site (metastable) within an unstrained bulk SiGe matrix. For all of these three configurations of iron, high-resolution Laplace deep level spectroscopy reveals sitting information as it is sensitive to local atomic configurations. In the present work, we focus, however, our attention on the alloy configurations not involving Ge atoms in the first-nearest shell of host atoms surrounding iron. It has been found that the alloy-induced electronic level shifts of these “no-germanium” configurations are about 0.98x eV, where x is the Ge fraction of the alloy, for all three forms of iron. If it is assumed that the iron-related no-germanium electronic levels do not shift on the absolute energy scale upon alloying, then the relaxed and unstrained Si∕Ge heterojunction must be of type II with the band offsets ΔEv=0.98 eV and ΔEc=0.57 eV. These results are discussed in the context of experimental values derived from strained systems.