David, you are great at strawman arguments in order to avoid the point, but I guess that is because you don't and can't have the answers. I will summarise the main point to make it as simple as possible, and hope you don't answer if it is just more of the same.
You try to make out that since the number of publishers is understated, that addressses my question. So lets go with an overstated figure - memorial attendance. Let's say that all memorial attendees believe current Watchtower doctrine and will be saved at Armageddon. That is 18,000,000/7,000,000,000, which is an insignificant, almost meaninglessly small number. It is most definitely not "many". When you teach that 7 billion people are about to be murdered by God, then 18 million is tiny.
Of course you will come back with, "the road is narrow" etc etc. But then every religion can say that, as every religion is in the minority. Your continual response that "many" believe Watchtower doctrine so it must be true is equally meaningless, as every religion can say that too, and it proves nothing.
Regaring YHWH, again you have sidestepped the question. There is not one known fragment of the New Testament, not a single one, with YHWH or its equivalent. If Jehovah really cared about his name, and really wanted people to believe Jesus used it, he could have protected it. You must have known that was the meaning of my question, but did not address it, as it cannot be addressed in any meaningful manner. Without wanting to sidetrack the issue, I don't believe there to be any weight in the arguement that since some copies of the OT Septuagint retained YHWH, then it must be in the NT; in fact the opposite. It shows that there was no global conspiracy 100 years after Christ, as you like to suggest, to remove every single instance of YHWH and destroy it just so that no one in our day would know it was ever in the New Testament.
Finally, since this is a core doctrine of the Bible, have you found anyone yet that believed Jesus was not their mediator prior to being indoctrinated by the Watchtower, and concluded such on the basis that he is mediator of only 144,000?