Hi Will,
Yes, you do played those notes separately. They are not tied. They function as the melody line while the triplets are added in addition. The second harp part outlines the melody clearly. (If you don’t have a copy of that to look at, you can find on at petruccimusiclibrary.com.) Having played this before, I would strongly encourage you split those measures between your right and left hands…the tempo moves at a clip and it’s next to impossible to play them with just one hand. Be sure to listen to the conductor’s preferred version (or, if they don’t have one, find a copy on youtube) so that you can get the melody in your head. Practice it with a metronome and consider playing along with the recording to get a feel for what it will actually sound like.
Best of Luck!
Elizabeth