I thought he meant credibility with cryonics advocates.
Yes, and I'm pretty sure I'm a typical enough example of a cryonics advocate for this to be a generalizable issue. If she isn't planning to sign up it really does at least communicate that she thinks it can't work -- that it's just an expensive funeral no matter who does it -- under present technological constraints.
Now, it's possible to think it can work and not plan to sign up. If you think it is too expensive of a trade-off on the risk-reward scale, or if you have an irrational fear of it. But Melody hasn't attempted to communicate either of these thing...
I recently found something that may be of concern to some of the readers here.
On her blog, Melody Maxim, former employee of Suspended Animation, provider of "standby services" for Cryonics Institute customers, describes several examples of gross incompetence in providing those services. Specifically, spending large amounts of money on designing and manufacturing novel perfusion equipment when cheaper, more effective devices that could be adapted to serve their purposes already existed, hiring laymen to perform difficult medical procedures who then botched them, and even finding themselves unable to get their equipment loaded onto a plane because it exceeded the weight limit.
An excerpt from one of her posts, "Why I Believe Cryonics Should Be Regulated":