I'm sorry, I messed up. If you only change the auto flags for the major and minor ranges, it will calculate them assuming the other parameters are correct. Since the other parameters were calculated for the very first dataset, they will not match new datasets, and the calculation of the major/minor range will get corrupted. You'll need tell the model to recalculate everything before querying the ranges.
I've attached an .zip file that contains an XML file that has all the flags changed in order to properly recalculate the anisotropy parameters. Use this file as the model source in Create Geostatistical Layer. Use the same XML path codes as above to query the major/minor ranges with Get Model Parameter.
Also, if you want to query the angle of the major range, use this XML path code in Get Model Parameter:
/model[@name='Kriging']/model[@name='Variogram']/model[@name='VariogramModel']/value[@name='Direction']
Sorry for the mess up, but this workflow should work now.