The third shows Gregory of Nyssa was a flat earther, speaking of the armillary sphere.   This is evidenced by "and then it returns to the same point in the CIRCLE."

Gregory of Nyssa believed in a spherical earth and it is silly to to try explain the quote away by claiming it is about an armillary sphere because such spheres have a sphere representing the earth in the center.

You may be interested in this excerpt from Robert Sungenis's book about Fathers of the Church who believed in spherical earth: https://www.scribd.com/docuмent/19644342/The-Consensus-of-Church-Fathers-on-a-Spherical-Earth

Funny how SUNgenis fails to include the Church Fathers' quotes who used Scripture to teach earth has the characteristics of a flat plane.  
Seems you missed that smoking gun.  

As far as St. Thomas is concerned, trickery happens.  All humans are subject, saints included.  However, I do not equate myself in any way with such a great man in saying earth is flat or that the Church teaches it (albeit in a subdued way), but rather, I have a huge advantage with around 800 YEARS of information and evidence he didn't have access to.  Scripture alludes to this saying: Luke 10:24  For I say to you, that many prophets and kings have desired to see the things that you see, and have not seen them; and to hear the things that you hear, and have not heard them.

There is no anathema for believing in spherical earth. But the evidence is persuasive to avoid the idea, and especially for reasons of Faith.

As far as saints teaching spherical earth, that is somewhat debatable because while a few saints had some explanations for their beliefs, they were hypothesizing about the sphere earth without the backing of the Church in a sense.  I say that because they didn't reference any Fatherly source, nor Scripture. Not to say they did what they did sinfully, they just assumed science proved otherwise.

Please don't insult me saying I contradict, or the Fathers contradict Scripture, even if you don't understand.  You have called me all kinds of names so I'm without much concern for answering this, but the Fathers and Scripture agree that the earth is supported by pillars, attributed to earth's foundation. In fact, the Church building is a microcosm of earth and the Church's doctrines are also known in scripture as the pillar and ground of truth, so there's a very real connection between the earth and the Church.  There is much to meditate on here but you'll have to read Christian Topography by Cosmas in order to see what the Fathers are saying.  Finally, the land masses we live on rest on the waters (oceans).  If you read the Fathers, it leads to understanding that there is a land/water/land situation going, apparently.  Land below (the physical bounds of hell) waters above that which makes up the oceans, and land resting on the oceans where we live.  Above that, is the firmament and above the firmament is heaven. Literally.  This is the general consensus among the Fathers.

The flat earth is not only not a psyop or nor is it stupid, it was well entertained in antiquity, favored by Scripture, and even taught by Fathers of the Church.  It is also scientifically and mathematically viable,  empirically provable by even simple tests, but also at the deepest levels, and it removes all stupid contradictions like "level means curve" when globalists speak of the surface of the oceans bending around a globe.

Except Scripture tells us it has pillars under it.