So you said "も" was being pronounced as ”あ” before and then you fixed it... how did you do it? (and you've probably already tried this but) did you try doing the same thing for those four notes? i wonder if resetting the preutterance and overlap on each of those notes would do anything
another thing you can try is running UTAU under administrator if you're not already. sometimes UTAU just acts weird and usually running it under admin magically fixes things, though sometimes that's not the case... but i'd give it a go if i were you^^ try your luck lol. also, sometimes the "restart your pc" advice actually works, so there's another thing.
and if all else fails i'd honestly just re dl her vb. this almost sounds like an oto issue but i've used some of Renri's vbs before and haven't had anything like this happen to me ??
basically i'd just restart my pc, run UTAU as administer, reset preutterance and overlap settings for the specific notes, and see if that works.