As we previously identified (link), Augustine had no concept of a continued bodily presence of Christ on Earth after the ascension. A very simple modus tolens logical argument shows that Augustine was not a Roman Catholic, in the sense of holding to the modern Roman Catholic view of the Eucharist. The argument is this:
Premise 1: If Augustine were a Roman Catholic, he would believe that Christ is not just spiritually present in the Eucharist.
Evidence in support of premise 1, Canon 8 from the 13th Session of Trent:
CANON VIII.-lf any one saith, that Christ, given in the Eucharist, is eaten spiritually only, and not also sacramentally and really; let him be anathema.
and this sacramental presence is defined at Chapter 1 of the same session:
In the first place, the holy Synod teaches, and openly and simply professes, that, in the august sacrament of the holy Eucharist, after the consecration of the bread and wine, our Lord Jesus Christ, true God and man, is truly, really, and substantially contained under the species of those sensible things.
Having established the first premise, we continue with the second premise:
Premise 2:Augustine did believe that Christ was just spiritually present in the Eucharist.
Specifically, for Augustine there were two kinds of presence of Christ, bodily presence and spiritual presence, as discussed at the links already provided above. Augustine clearly taught that the ascension deprived the disciples of the bodily presence of Christ, and that instead they had his divine spiritual presence.
Conclusion: Augustine was not a Roman Catholic.
This conclusion necessarily follows from the premises, as a matter of logic.