If you're in mixer signature campaign, now you don't have anything. There is no need to show initiative. Mixer campaigns is allowed on Bitcointalk as long as theymos won't decide different. If one day he will decide to ban mixer campaigns, then you wouldn't have to make decision to leave campaign - all mixer campaigns simply would end then.
What theymos told to staff members is different story. Bitcointalk staff isn't same thing as regular members - they can be considered as employees of Bitcointalk. Emplyees of Bitcointalk advertising ''money laundering'' related stuff - it can bring problems for Bitcointalk. While regualr members can continue advertising basically everything, not just mixers, but also all kind of scams.
I don't think theymos will stop Mixing companies to advertise their products in the forum, and the only time theymos can do that is when a president strongly confirmed that the mixing is a scam or money laundering company them at that time he might make a pronouncement to stop his members which he has done not to participate but to stop the company in the forum is what I can't not tell because All the allegations level against 1Xbit both the forum and outside the forum yet 1Xbit is still running well in forum therefore, the mixing company might still run in the forum but limited members will like to promote such a company.
And not Mixers companies are bad or have a fraudulent activities, some of them are genuine, so we can't use what happened in one to generalize others.