This happened like twice as we're playing. The first time, it happened to a CPU Luigi, who is dumb anyway. He got a gold ball
The second time it happened, my sister just scratched the first card and she got 1st prize. She got a 100 coins, and it helped her contribute to having 999 coins. It was also in Bowser's Gnarly Party
And one time, someone (a CPU) DID win the lotto ticket on the last 5 turns. You expecting something awesome? Nope, you just win a star. That's it.