More open, rested eyes - Is this result from ptosis surgery or fat grafting? (Photos)

Assuming it is the same person, no, ptosis surgery did not accomplish this result. The before eye pair does not have ptosis. What it does represent is central levator disinsertion with a compensatory eyebrow elevation. The after image shows an individual with a relaxed eyebrow and more volume in the upper eyelid sulcus. Essentially the before is an innie eyelid (synform fold) vs the after that is an outie eyelid (antiform fold). Grafted fat will not fix your upper eyelid fold and can cause some pretty severe complications. Fillers are used to fill the sulcus but these never look natural. I perform crease lowering surgery that is able to convert an innie eyelid to an outie eyelid. A detailed in person consultation is needed to determine if this type of surgery would be right for you.

First, I'm not sure if the "before/after" you have posted is the same person, because the eyebrows are different and the amount of ptosis reduction would not create that dramatic a change in tarsal platform.
In moderate to severe ptosis, as the eyelid is lifted, and the compensatory lifting of the brows relaxes, the tarsal platform will decrease significantly.
But the ptosis exhibited in the upper photo is mild and it is quite difficult to say that the brow elevation is that significant. So if the above photo is you, I doubt that ptosis repair alone will get you to the photo below.
Make sure you consult with an Oculofacial plastic surgeon (oculoplastics) that not only has experience in internal and external ptosis repair, but also does fat grafting and other aesthetic oriented procedures, as this may require combined surgical procedures.