Sure, who is 'Devil's advocate', basis of previous debates. On the balance of previous, you're a hard nut to crack, considering previous evidence presented, with regard to the neck and TN, although at this point you should be wavering despite your previous dogmatic responses.
With the evidence, on the whole, you would seem to be arguing against alot of intelligent people previousley quoted as authors in the references provided.
In asking the question "then what specific treatment protocol would seem to be indicated, and where is the medical evidence that it works without harm to patients? ", would seem to be asking that I remove the corners of the square to invent the wheel, already done ( otherwise patent pending!).
A medic should consider the neck as a possible cause for TN, as the trigeminal nerve complex extends to the upper neck, indeed the lower neck can influence the upper neck and as such may be also implicated. Evidence has shown this.
As such, there would be no specific protocol beyond any other that would treat neck dysfunction/ pathology/ problems.
The majority, I believe, of medical interventions, for cervical/ neck dysfunction have already established risk factors in the research literature, those that could be argued haven't, would not find it hard to compete wth recognised risk factors for MVD- death.
Medics up and down, are performing procedures for cervical/ neck dysfunction with evidence. The approach for suspected TN due to a cervical cause should be little different for cervicogenic headache for example.
Patient narrative,consultation, differential diagnosis, examination, further diagnostic procedures if required ( blood tests, imaging etc.), diagnosis, treatment, reassessment; continuation of treatment or referral, is adequate for TN ( if considering the whole trigeminal complex including the neck), but is unfortunately ignored by many medics, due to ignorance of the anatomy, or preconceived ideas.
Feel I've removed the third + corner of said square, we should soon be rolling.