I was wondering about the catch light also. You did catch some in the second shot, but not the first.
You might have to try playing around with the position of your light source. Maybe have the light source closer to the subject.
You should be able to get good catch light with a diffused light source. However, from your description of the light source you made, I have a feeling that it might actually have been too large. Furthermore, having it floor-standing means that the flash always fires straight ahead, and you don't have much control on the height of the light source.