Lunch Money Big Combo + Roundhouse

me and my friends were playing and this situation came up

Player A played Big combo + Elbow + Roundhouse
Player B Blocked the Elbow and Dodged the Roundhouse

now if dodged would player C take full damage from Roundhouse and big combo but nothing from the elbow or would he take half damage because the elbow was blocked by player B??

Neither is correct.

Big Combo doesn't let you play two other attack cards, or to verbally declare that you are using two other "real" attack cards (including their effects).

Big Combo (emphasis added):

You just get the describe the two-pronged attack and your opponent must try to defend (or eat) two seperate blows.