3:53:44 Funniest part which you missed in that mini-game: if you have enough momentum, you can tap double (which is why Marcus tells you that you are going wrong way) and later triple time to same direction getting more momentum to your swing movement, making this section faster.
Also to clarify 3:28:56 why she did that; Well her husband died by Black mage early in the raid, and she just saw an opportunity to take revenge for her husband and she just took it... with unfortunate result. I guess she loved her husband more than her children.