insurance company sued for $5m casino fraud

The Miccosukee Tribe of Florida filed a lawsuit against it's own insurance provider Great American Insurance Provider in an effort to recover $5,300,000 that was stolen at its Miccosukee hotel and casino & Resorts in Miami-Dade County as part of a sophisticated embezzlement operation. Stealing, computer crimes, and money laundering were found to be committed by four employees, three couples, and a fiancée.

 

[GamblingBoy]

I really don't understand this episode. What has the insurance company got to do with the embezzlement of over $5m?. Whose employees committed this acts, the insurance or the casino?.
In whose premises this act was perpetrator?. This and many more of the puzzles the reviewer should have solved.