I have yet to see it cited that the veil completely disappears in 4th-density.

[anagogy]

I believe Ra mentions that wanderers are inherently dual-activated?

No, they elect to have 3rd density mind/body genetic connections. So a wanderer is no different than any other 3rd density, except in the spirit complex, which allows them a certain unconscious bias towards truth in many cases.

Also, how can 4th-density negative entities exist if there is apparently absolutely no veil? Ra mentions that societies with no veil were positive.

There would be no negative polarity if our evolution through the densities had been veil-less, however, moving through the evolution of 3rd density with a veil intact has taught certain entities to love falsity, or illusion, and once that taste has been acquired, it doesn't matter if they know "we are all one" or not, they are fully aware of this fact, and reject the greater self in favor of the separated self.

87.11 Questioner: I’m sorry for getting confused on the question here and not asking it correctly. There is a philosophical point of central importance to me that I am trying to clear up here. It has to do with the fact that fourth-density negative seems to be aware of the first distortion, and they are in a nonveiled condition. And they seem to use this knowledge of the first distortion to maintain the situation that they maintain in their contacts with this planet. I am trying to extract their ability to understand the mechanism of the first distortion and the consequences of the veiling process and still remain in a mental configuration of separation on the negative path. I hope that I have made myself clear there. I have had a hard time asking this question.

Ra: I am Ra. The answer may still not satisfy the questioner. We ask that you pursue it until you are satisfied. The fourth-density negative entity has made the choice available to each at third-density harvest. It is aware of the full array of possible methods of viewing the universe of the One Creator and it is convinced that the ignoring and non-use of the green-ray energy center will be the method most efficient in providing harvestability of fourth density. Its operations among those of third density which have not yet made this choice are designed to offer to each the opportunity to consider the self-serving polarity and its possible attractiveness.

As Ra stated in another session: some love light, some love darkness. All these experiences are available. Each chooses their picnic.