No, equality won't help the situation. The problem is that the winner among 5 participants isn't to blame for having so few competitors. He might have beaten 50, but there simply aren't that many. Therefore, punishing him would be unfair.
Added 3 minutes later
Therefore, a different scoring system should be implemented if the number of participants doesn't reach the minimum quota. I suggest creating a kind of reserve prize fund for such cases.
Все люди - братья, но в каждом из нас спит волк.