You answered it yourself.
Cindy is Jim’s daughter.
He was connected to Marley, and the guy who was documenting all of this was named Don Bolles.
Look that name up. You’ll be shocked.
However, my point was, it's not John's dad, Megan's grandfather, but her father which you stated that it was actually her grandfather who was the fraud.
What am I missing here? 🙂