The issue is that those portions do not have the text as immediate descendants of the link. Since I have never worked with the background-clip property before, I am not sure how to fix it. However, if I had to guess, I would say the solution would be to apply the background image to the immediately enclosing element of the text.
The numbers are enclosed in em tags and the text after them are enclosed in span tags. I just did a quick check and applying the background settings to those will get the text to appear. However, I am not sure what to do about the animation part.