1. In the tcg, there are cards called 'erika's dragonair' and 'erika's clafable'; both can be gotten from the game corner in celadon city. this implies she other gamled her way for them, bought them with her vast amount of money, or convinced her parents to buy. however they didn't appear in other parts of the franchise, so she probably released them once she realized pokemons shouldn't be prizes for gambling.
2. Being celadon gym leader, she probably figured out tr has a base in the city, no matter how sleepy she is. however, either because giovanni was a fellow gym leader, tr coerced her as grass pokemons ware poor match to tr pokemons, her own past in the game corner was in question, or was actually in cohoots with rockets, she didnt act to vanquish them.
3. maybe she was biding her time and training till she could do so. maybe she didnt act because either she herself or her rich parents ware working with tr. maybe even her postion as gym leader was not earnestly earned, tough her parents money could probably deal with it.