I'm not sure what the extra prizes are.
The only thing I see in the article is that they will select 1 player to join them to play on a yacht.
https://www.pokerstars.com/en/blog/...treamBoat&utm_medium=Social&utm_source=Client
"Here's how it will work: the streamers will be giving away tickets to a private tourney on
pokerstars on March 5 (with $2,500 added to the prize pool, because...hey, again, why not?). The six finalists from the Streamboat Tourney will be in the running to go on the trip to the Virgin Islands. The four streamers will pick one of the six finalists to be their guest.
If you don't win a ticket on one of the Twitch streams, you can still get one in a special promotion on PokerStars. If you make a deposit using the code Streamboat, you will get a ticket to a March 4 freeroll with $2,500 in prizes and 20 seats to the private Streamboat tourney."
It doesn't say how they will choose someone from the final table. That poker player Bill Perkins is a hedge fund manager, and already a multi-millionaire outside of poker.