Can I throw in this brainstorming thread this theory video? What do you think?
No, I don't buy it. There are a lot of other factors involved. Titans are only a part.
They are a force of balance. The Fade and the unchanging world. I believe the Titans moved around and "shaped" the world in order to compensate for the changes being made by the Evanuris and Elvhen People who took form and claimed the earth as their right.
This brought the Titans to their attention, which is why they started hunting them and learned of lyrium and it's enhancing qualities. I don't believe Mythal is an agent of the Titans either, her plans revolve around what was wrought by the Evanuris and what Solas plans to do.
I believe the veil is what brought the Titans into a dormant state. Without The Fade interacting with the unchanging world, their role as Shapers of the stone and as keepers of balance isn't needed. They are cut off from their purpose as well as the source of their consciousness. This is why they haven't created anymore Dwarves and most likely why the Sha-Brytol are so lost and confused. The fact that the breach is what caused the Titan to "panic" lends credence to this train of thought.
The Elvhen people were products of The Fade and were spirits before they found a way to take form.
Given the codex Old Elven Writing: "Their workers scurry, witless, soulless, this death will be a mercy" we know how the Elvhen people regarded the Dwarves, they pitied them and didn't even consider them "real" people. Their views basically reflected Solas' perceptions of modern Thedosians. They felled Titans before the veil. I doubt they (The Titans) held any sway over Solas or any of the ancient Elvhen.
As for Sandal, he very well could have been, or is connected to a Titan. As for "not enchantment" i.e. "magic", it rather seemed to be a frost spell, "Cone of Frost" to be precise, rather than him turning the ogre to stone like Solas did Qunari, if you watch carefully.
Speaking of Qunari, we still don't know their circumstances, though it's implied they are a mixed race infused with bred with Dragon blood who were a mistake. It's implied the Kossith, whether a culture or an actual race, were also "horned" and I believe they served as slaves during the Tevinter Imperium when they left from the east, 15 years before the Magisters reached the Golden City. I think they were used as blood sacrifices and slaves to fuel powerful blood magic (as we know dragon blood is especially powerful).
We also have no clue what caused the blight in the first place, only hints that it was due to the Evanuris unleashing something primordial is their greed. The Forgotten Ones are also another factor that has yet to come into play.
from what we understand of Geldauran's claim, they are not Titans, nor are they agents of the Titans. They could be however, involved in having unleashed, created or harnessed the blight.
Besides, if it was that simple the series wouldn't have much of a shelf life in my opinion, meaning, I would lose interest in the lore if this was the case. The song from lyrium is said to be different than the calling of the Old Gods, which is perpetuated by the blight, not red lyrium, meaning the blight itself is of a separate nature.
The Black city is said to corrupt spirits with the taint who wander to close to it, meaning it is a sickness of the soul also made physical when it hitched a ride on the Magisters once they breach the Golden City. This is why Red Lyrium i.e. blighted lyrium can infect people "psychologically" simply if someone gets near it compared to normal lyrium, where its effects on the psyche require "physical" contact.
Also, Dwarves were created by the Titans and once held a symbiotic relationship with them as Valta does, this is why Dwarves still have a lingering connection, like whispers of something once lost, the stone sense.
Other races can only hear the song when handling lyrium such as Templars and mages. The song itself also seems to repel Darkspawn, interfering with the calling.
In World of Thedas Vol. 2, it's also speculated that their are a lot of suspicious things revolving around the world such as the Voshai, mysterious traders from the west who apparently are led by Dwarves, who apparently hold standing in their culture and are often seen as ship captains. Then we have "Parladians" from the Boeric Islands, who could or could not have magic specialists akin to the seers of Rivain that specialize in concealment spells that can mask a whole islands "location". The Tirashan to the West also holds many mysteries, including Elves that seem to worship The Forgotten Ones. We have the "sunless lands" to the north, described as a hellish wasteland of Ice and snow home to Chasind exiles which may or may not have formed their own tribes.
To the East, the supposed Kossith/Qunari homeland of which we know next to nothing. It is said many who ventured forth have disappeared, some due to immense sea creatures, others due to what they found on the mainland. Drakon's Prophecy seems to imply a war was fought there with tooth and claw, sword and bow, brethren who after a time, could not be distinguished from one another cursed, generation after generation. Perhaps this was in relation to what happened with the Kossith and what led to their "dragon blood". If the Inquisitor is Vashoth, Kieran will either declare that their blood "doesn't belong" to the Inquisitor's people and express his sorrow at what happened to the people, which could also be in relation to what transpired in the East. The Par Vollen Pyramids are yet another example of mysteries waiting to be explored and explained.
All of this explain there are still many pieces of the puzzle left to put together and the Titans are but a piece, not the frame which holds it all together.