I think the idea is that people were voting for who they wanted to SEE, not necessarily to 'help the team win', but instead to increase their enjoyment of the event by having some of their favorites be there, especially since only the top score from each discipline counts toward the team score anyway. Does that make sense? Can you understand why someone might just vote for who they want to see, not for who they think would score the best? If the idea was just to get who would score the best, probably the 'most logical' if still imperfect solution would be to invite the person who has the highest seasons' best score.
People can vote for whatever reason they want to vote. But I still don't think Soyoun would have added much if anything to the team or the event.

The sad part is I am not even sure what they meant to say... she isn't 2 time champion of anything except for TEB...