Some managers would have tried to rinse every last ounce of personal benefit or gain out of a campaign that was being hit with scam accusations but full credit to Hhampuz for taking steps to minimise impact at a very early stage.
Regarding members leaving the forum, I think that is simply overstating something that is a remote possibility. In the end, it is the income from signature campaigns that is keeping them here therefore they would rather wait and join another campaign rather than jump ship and migrate elsewhere. (Some might use the opportunity to join another forum whilst still remaining active here).
I applaud the manager for caring about the users over caring about his pocket. I think everyone should be the same way who is managing a campaign, but that's not how it goes.
As far people leaving the forum, that's their choice. There are tons of companies out there still running campaigns, sig campaigns come and go. Users still need to stay active if they want to have a chance to join the next campaign that comes. Inactive accounts are normally passed up.