[SPOILERS] Stormblood Ending

[Theodric]

Aulus - the scientist responsible for much of the experimentation throughout 4.0 - was not a man who Varis approved of, nor did many within Garlemald's capital. He said as much himself and it was only due to Zenos' interest in Aulus' theories that the Resonant and other experiments came to be. Varis has also been established as a pragmatic and honourable individual - he defended Regula against those who spoke out against him and allowed Regula to rise up through the ranks due to his own merit rather than because the pair were good friends.

Zenos was not operating for the betterment of Garlemald. He made that clear with his own words.

[Rosenoire]

Aulus - the scientist responsible for much of the experimentation throughout 4.0 - was not a man who Varis approved of, nor did many within Garlemald's capital. He said as much himself and it was only due to Zenos' interest in Aulus' theories that the Resonant and other experiments came to be. Varis has also been established as a pragmatic and honourable individual - he defended Regula against those who spoke out against him and allowed Regula to rise up through the ranks due to his own merit rather than because the pair were good friends.

Zenos was not operating for the betterment of Garlemald. He made that clear with his own words.

This part in the scene with Varis calls that into question:

Elidibus: You do not mourn his loss? …You surprise me, Your Radiance. He was your son and heir…and an irreplaceable test subject.

Varis zos Galvus: I know what he was. Monsters are not made for thrones.

That sure sounds like Varis worked with the Ascians and used his own son as a test case.