I'm sorry. I did read your post properly. 93.3 keV isn't the energy of the photon though, it's the recoil energy of the nucleus and the gamma ray.
Egamma + Knucleus = 93.3 keV
Is that not right?
Also, how do you get the 400 odd m/s? If 1/2Mv^2 = 93.3 keV
9.33e4 = .5(67(9.315e8))v^2...