Do I really have to complete this mini game? Will I still have a 100% completion even if I skip this one??

and about the story completion, It's my first time playing the game and I really want to get 100%. I gave the sphere to the youth league w/c made it possible for me to complete the story. Im now in Chapter 3, i'll just have to finish Ixion, but still at 46%. Is that normal?