Not necessary, to be a certified member on true nudst you have only to send to the direction of the site a photo of you clothed and a photo of you naked with a paper on wich is written true nudist and your nickname, the certiification says that you are a real person but not what's your intention or what you'll do with the charged photos, i found some certified member on true nudist in the other site true swingers.
The only way to use true nudist safely is don't charge any pic.