You seem to be misunderstanding. During the ~29,999 losing bets the bankroll grows by a factor of more than 100, so when the lucky bet wins 99% of it the bankroll is still bigger than at the start.
the problem I see with this bet is that even the chance is 1 in ~30k the user can win it in his first bet before the 29,999 losing bets. or what do I miss here?