The story is fiction. These aren't.
Every part turns on a real money rule. Here they are in plain English, with sources. US federal rules, not legal or financial advice.
Seen in Part 1Why is a cash-out offer less than my slip is worth?
A cash-out price is set by the sportsbook and includes its margin, so it pays less than the slip's fair value. On a coin-flip last leg, a $2.4 million slip is fairly worth about $1.2 million; an offer of $1.1 million keeps the difference for the book.
Seen in Part 1What is hedging?
Betting the other side of your own bet so you profit whichever way it goes. It costs real money: locking in a $2.4 million slip on an even last leg takes a stake of roughly $825,000.
Seen in Part 1Can a sportsbook limit how much I bet?
Usually, yes. Books can lower a customer's maximum bet, and they do it most to bettors who win. A few states restrict limiting purely for winning.
Seen in Part 1Do sportsbooks report big wins to the IRS?
Yes. When sports winnings minus the wager are over $5,000 and at least 300 times the wager, the payer withholds 24% and files Form W-2G; a copy goes to the IRS.
Seen in Part 1Is the 24% withheld all the tax I owe?
Not on a big win. Gambling winnings are taxed as income, and a win this size lands in the 37% top federal bracket, plus any state income tax.