An un-buffered saturated solution of germanium sesquioxide has a pH between 2.2 and 2.6.  Based on the known structure, the amount of NaOH needed to neutralize the product is a simple calculation.  Dangerous levels of inorganic forms of Germanium will produce a low titration.  A mixture of Vitamin C and germanium dioxide in correct proportions to pass titration will invariably fail the elemental analysis, HPLC, X ray fluorescence, X ray defraction, IR and solubility.

Keep in mind that there are derivatives of germanium sesquioxide in the form of salts.  These are not harmful but will also give a low titration.