In this case, the rights of a player competing for a rating will be infringed. After all, while completing a campaign, they cannot know how many final submissions will be received and whether a quorum will be reached. If no rating points are awarded for unofficial tournaments, I can say for myself that I am unlikely to participate.
If the rating is awarded in an unofficial tournament when a quorum is reached, I might still take the risk of playing. If the quorum is determined by the number of registered participants, I will definitely know whether or not to play in this tournament. That's the situation.
Interesting scenario... :) I am, of course, in favor of a quorum, but not exactly as you describe it. Let the difference between official and unofficial tournaments still lie in this. In principle, I am in favor of awarding rating points in an unofficial tournament, but only according to the quorum rules, and if only one person submitted a save, they knew that they might lose. There should definitely be a difference.