Would my channeling my client’s cognitively impaired son [name withheld] allow me to speak with him and would this be productive?

Yes, of course this can be done. As we have told you and others you consulted, the true person and their consciousness is always present and connected to the physical body as part of the ongoing life experience. When there is impairment, it is impairment of the body, not of the consciousness of the being per se. Even when there is neurological impairment, this is not an impairment of consciousness, but merely the expression of consciousness to others through using the body in some way in signaling, whether through body language or speech. Depending on the level of cognitive impairment that impairs the brain and its circuits, there may be more or less outward appearance of perception by the sufferer, but the consciousness will always be present and understanding what is happening. You will be able to connect and speak with him, and this could be quite rewarding. The consequences for revealing this may well be problematic and would put you in the center of a firestorm with the volatility of this family. There are potential circumstances where this could be brought to their awareness, but this might be a quite risky proposition with the strong religious views, and the lack of belief in such paranormal capabilities, and your outreach from the heart would likely be interpreted as misguided at best and an attempt to exploit them at worst. So this would not be the best first example to try in connecting with a person with impairment, but you could do this in order to have a discussion with him and explain the situation and go from there.