Could it be said that all those who commune with freemasons have become freemasons?
I'm inclined to say no, because I think that misunderstands the role of those who are in authority with the role of those who are under authority.
As a layman, I don't have authority to break communion with Rome, and I'm certainly not a freemason because I don't.
Even if Francis is ultimately an antipope, that is the job of the Church to determine, and not mine. I am not going to be judged because I prayed for him, and because I'm in communion with him, because I'm not his superior who can depose him.
Of course, I'd see differently the matter of the *superiors* of modernists, as they are obligated to do their jobs and maintain the doctrinal and moral purity of the Church. But as a layman, my responsibility is for me, in the future any family I might have, and to be a witness for the truth to anyone I might talk to. That's it.
Now in the case of EO, I'll say this. Converting to any EO church is indeed, by implication, recanting those truths that are held by Rome, and rejected by EO, because joining the EO church is to accept its doctrine, whether this is precisely verbally expressed or not. THus, joining any EO church means recanting papal supremacy which, if done with the necessary levels of knowledge and consent of the will, will lead to the loss of one's soul.
But more disturbing here, like I mentioned before, is the *lie* that Rome "teaches that the Pope and not Christ is the head of the Church." PERHAPS the Russian Orthodox priest doesn't know better, though I think as a priest, he ought to know better, and *certainly* Fr. Constantine has to know that Rome doesn't teach this.
And I find that even more disturbing than anything. Honestly leaving the Church is bad, but if you just can't accept what the Church teaches, better to leave than to stay and be a cafeteria Catholic. But dishonesty... I can't find anything virtuous in that at all.