Is there a reasonable chance of him seeing an improvement if we do a few more subconscious channeling sessions? I don’t want to give false encouragement.

This could be of benefit to do, but will not be able to shift things on its own. As you know, all healing is for the better that can be done, but in terms of priority, repeated Protocol work to add additional intention with the repetition would be of greater benefit to the long-term goal here of having him drop off of their roster and no longer actively harmed in this way. That is doable, but will take time.