...St. Thomas moved things even closer to the Reductionism end of things away from the Platonism approach. But he was still vexed by the problems inherent in Reductionism. His solution, as presented in the Summa, was to fall back on the "science of vision" explanation:
... Hence all things that are in time are present to God from eternity, not only because He has the types of things present within Him, as some say; but because His glance is carried from eternity over all things as they are in their presentiality....(ST, prima pars, q. 14, a. 13)
It's a remarkable attempt to reconcile the two, in that it doesn't really place God "outside of time" as much as it places all times in God. But it suffers from a lack of precision around the word "presentiality", which in its common understanding drags things right back into the Platonism approach -- because it ultimately means the same thing: God sees the future as present.
Since I don't understand his criticism, my criticism of this is likely to be wrong, but here goes:
Strictly speaking, it's improper to say "God sees the future," since objectively there is no such thing as "the future." There can't be, because all objectivity comes from God, and God has no future, being "outside of space-time" or, equivalently, unchanging. It's not as though, although all of time is somehow "present" to Him, God is tracing the cosmic timeline with His finger to mark what we experience as "the present." There is no, there can be no, temporal moment that demarks past, present, and future in eternity.
Since as was shown above (9), God knows all things; not only things actual but also things possible to Him and creature; and since some of these are future contingent to us, it follows that God knows future contingent things. [emphasis added]
It only makes sense to speak of "future contingent things" relative to us, to temporally bound creatures. When St. Thomas refers to future contingent things relative to God, he says "things are they are in their presentiality."
Fr. Dowd thinks this is a problem because to him "things in their presentiality" means "future things as present things," and for a Reductionist (which both Fr. Dowd and St. Thomas are), future things don't exist. But the one doesn't mean the other, because again there is no future for God. There are no -- there can be no -- future things to God, and if God knows things that are future to us... well, He is, after all, God.