We report on emission channeling experiments on ion implanted Fe, Cu and Ag impurities in germanium and ab initio total energy calculations. Following common expectation, a fraction of these transition metals was found on the substitutional Ge position. Less expected is the observation of a second fraction on the 6-fold coordinated bond-centered site. Ab initio calculated heats of formation suggest that this is the result of an impurity-vacancy defect complex in the split-vacancy configuration.