Checking their campaign pay rate, they offer one of the highest. I don't blame them if they want to attract great posters, but marketing is not something you do short-term and you will get instant results. There should be a phase, people will notice, then they will recall, until it plays on their mind over and over again when thinking of a platform.
Familiarity is very important in marketing, so duration plays a big factor; one week is just too short to establish a recall. I'm sure they will do another round if they want to be competitive in a highly competitive niche.
Am not expecting them to conduct another round or more of signature campaigns in this forum since they don't seem particularly interested in it anymore and are more focused on other stuff like review campaigns etc.
It's definitely possible for sites to become popular even without long running signature campaigns through other forms of marketing for a long period of time.