I just thought of something, if there's room for 4 more gym leaders, what happens if only 3 (or less) of the challengers vying to be gym leaders win their matches against the gym leaders they chose? In other words, if there were only 4, 5, 6, or 7 gym leaders after all this, how would the remaining spot(s) be filled?

To me, it really reminds me how much of the Jeopardy! tournaments work, in addition to the 5 winning semi-finalists, the remaining 4 slots there are given to the 4 non-winners who got the most cash among themselves.