<human>: Give me a shortened version of the text

Before I proceed, allow me to verbalize that I'm not trying to get out of responsibility here; I realize my fault.  I only want to learn from the [often times brilliant] reddit community the best way to proceed.

The story:
My dad is a physician and has his own practice in a small town.  Some time ago (maybe 3 or 4 years ago) he asked me to make a website for his practice (purely informational, we don't sell anything on the site), so I learned HTML and whipped up something basic.  The site itself is pretty amateur--it's small, sort of sloppy, plain.  Most of the images used on the site were of him, his staff, or the office, but ONE picture was taken off Google (a picture of a pregnant woman smiling).  I thought nothing of it at the time.   The site hasn't been updated in a long while, and (no offense meant to my dad or his practice) I doubt the site gets that many hits.  His practice isn't that big.

Today my dad receives a letter in the mail from an image stock company (Masterfile) informing us that we have violated copy infringement over the use of this image.  Instead of initiating legal action, they are offering a retroactive license for the image provided I remove it from the site and pay a $2,010.00 fee within 10 days.  Otherwise, a legal process ensues.

I'm a poor grad student--I don't have $2,010.00 to shell out.  Nor do I want my father to drop 2G for is effectively is my fault.  And I don't understand the law enough to know my recourse. Is there any way around this?  What's the best way to proceed?  I'm obviously taking down the picture, but I'm unsure if there's a loophole I can probe.  Call me naive, but two thousand bucks seems like a lot considering the site is so small-time and probably gets no hits.
<bot>: I used a copyrighted image on my dingy website and years later I'm being asked by the copyright owners for $2,000 in damages.  Looking for a way out.