I'll go out on a limb here and tell you Getty's response:
"The image in question was a screen capture used for portfolio purposes to generate revenue for the infringers business, it does not matter that the image appeared somewhere else. The image appears on your web-site and there is no valid license agreement...yada, yada, yada..
I might be inclined to reduce the response time from 14 to 10 day, mail it and date it on a Friday, with any luck it will take a few days to get there, and you've already lost sunday, you might just get lucky and they might miss your deadline.
+ 1 for keeping it short and simple. I agree about admitting nothing as well as not getting into the fair use argument.
If you're going to quote, quote from Getty CEO Klein (vids on the home page of ELI) where Klein encourages people to use Getty images as long as they're not used for a commercial purpose. It seems to me that your wife fits this category perfectly. Let's see what kind of BS reply a Getty intern will have for that one.