How would he be able to do that any more than any other member? As has been said before, he would be subject to the same forum rules as everyone else. The rules aren't perfect, they never will be, but the mod team, in applying those rules, have done a good job in preventing the forum from being derailed so far.
Currently, Dr Gundersen could, if he so desired, sign up using a pseudonym and an easily obtained anonymous email account and we'd be none the wiser, as could any other BPS supporter. In fact, the chances are that this has already happened, in my opinion, as we know it happened with PR. The safe space is created through application of our forum rules by our mod team, not through an attempt to restrict "undesirables" to a small area of the forum.