Fairly certain this is all original custom content.
The art style doesn't match up at all. The image also doesn't blend too well in the announcement graphic.
Not only that, but the skill icons are of obvious lower caliber, no offense to whoever created it, Gravity's spriters are just on point.
The image of the sprite is too blurry for me to really analyze it properly, so no comment there.
On top of all of that, I see no mention of any of this on kRO.
Some time ago Gravity released a second batch of Doram skills, but it's not a new class at all, it was just an extension of the class post-100.
To close this up, I doubt Gravity would further buff Dorams before giving some love to the existing jobs.
But hey! I could be wrong.