I was as confused as you, but then I went back and plowed through the whole thread.
People (internet sleuths) have cleverly found out the ID of Foley's boyfriend. From there they researched, learned his DOB, looked at the dates on the IM's from ABC, and learned he was 18, not younger as originally reported.
So it was a "Sex Chat" between consenting adults.
Still sleazy and filthy, but apparently totally legal.