Trying to understand what the vcv vowels are

first off, are you recording a 7 mora, 5 mora, 3 mora, 2 mora or anything else?
whichever it is, you should be able to look at the string names and rerecord the vowel strings. Looking at the oto can also help~

ahh no xD
mora is simply the amount of sounds on a string c:
there's 7 mora (Ritsu, Ruko, and more) for example: kakakikakukeka
there's 5 mora: kakakikaku
there's 3 mora: I have no idea what they look like :,D
there's 2 mora: aka, aki, aku, ake, aka

depending on the mora, it may be annoying or easy to rerecord c: