DUBSTEPPED asked, "Am I wrong?"
Yes, in my opinion, at this time on this issue, you are in error. You said, "I was under the impression that CTR's group of Bible Students were comprised of people of all different faiths and that it was okay to mix." (Emphasis mine.)
ALL different faiths? How many Muslims?
CTR thought it was his mission to gather the members of Christ's "Bride Class" from the various churches of Christendom into which they had been scattered. They were all nominal Christians who were to be prepared for their Everlasting Marriage in the world beyond.
This brings us to the question, "When we talk about Masons or Freemasons, what do we mean?"
This is what I mean:
From Wikipedia, "History of Freemasonry"
Since the middle of the 19th century, Masonic historians have sought the origins of the movement in a series of similar documents known as the Old Charges, dating from the Regius Poem in about 1425 to the beginning of the 18th century. Alluding to the membership of a lodge of operative masons, they relate a mythologised history of the craft, the duties of its grades, and the manner in which oaths of fidelity are to be taken on joining. The 15th century also sees the first evidence of ceremonial regalia.
There is no clear mechanism by which these local trade organisations became today's Masonic Lodges, but the earliest rituals and passwords known, from operative lodges around the turn of the 17th–18th centuries, show continuity with the rituals developed in the later 18th century by accepted or speculative Masons, as those members who did not practice the physical craft came to be known. The minutes of the Lodge of Edinburgh (Mary's Chapel) No. 1 in Scotland show a continuity from an operative lodge in 1598 to a modern speculative Lodge. It is reputed to be the oldest Masonic Lodge in the world.
Alternatively, Thomas De Quincey in his work titled; Rosicrucians and Freemasonry, put forward the theory which suggested that Freemasonry was possibly an outgrowth of Rosicrucianism. The theory had also been postulated in 1803 by German professor; J. G. Buhle.
From Wikipedia page on Rosicrucianism
Rosicrucianism is a spiritual and cultural movement which arose in Europe in the early 17th century after the publication of several texts which purported to announce the existence of a hitherto unknown esoteric order to the world and made seeking its knowledge attractive to many. The mysterious doctrine of the order is allegedly "built on esoteric truths of the ancient past", which "concealed from the average man, provide insight into nature, the physical universe, and the spiritual realm." The manifestos do not elaborate extensively on the matter, but clearly combine references to Kabbalah, Hermeticism, alchemy, and mystical Christianity.
I will offer that the esoteric nature of Freemasonry makes it incompatible with CTR's teachings, also that the laws governing Freemasonry are extra-Biblical and to be shunned.
That is what I think right now.