You don't mention what caused her to strike the other two times. Were the cats nearby outside of her cage and she struck the glass? Or was this you by yourself trying to take her out?
Really dislike labeling the snake as aggressive when she's one of two things. Defensive or HUNGRY
My other concern I don't see mentioned is how dangerous even putting the animals in this situation is.
You don't mention the size of your Red tail, If she's a grown girl she can easily do a lot of damage to your cat. A warm fuzzy thing that darted up to her.
Also the opposite is true in you cat can really do some damage to your snake.
You cannot keep other curious animals nearby while handling snakes alone. It's very difficult to safely keep an 8 ft snake in one hand and shoo the cat away with the other. Someone can still get injured and it could absolutely be you as the middleman.
Take this as a learning experience. I hope your Red tail warms back up to you as her keeper.