Doppler frequency formula (for HB100)
Without even trying to actually do the same calculation as you: there's a peculiar factor of 3.6 between your result and the application note.

Chances are, either one of you or the app note author forgot to convert km/h to m/s. 

(1 km/h = 1000 m / (3600s) = 1/3.6 m/s)