Just from the free WOF spins, you would not win a lot though. The daily WOF spins you got for the premium membership were more interesting and rewarding (I think I gathered around 150,000 RP from that). Leaving a negative trust is maybe too harse as they are still paying but maybe a neutral tag that can change later to negative if the issues keep persisting and if problems with payments would occur might be the best?
Things were good as long as they cared about their users. Even I had received around 70k RP from WoF spins back then.
But since the issues started popping up, it seems they are not even bothered about the users and hence the negative trust.
They should at least come upfront to speak about the issues let alone address them and fix them.