Of these songs, the one that affects me the most is Volveré.
The first few times I heard this song, it sounded like parts of it were sung out of tune, particularly at the ends of phrases, but the song still had a strong enough musical effect to give me goosebumps. The sense of being "out-of-tune" derives, I believe, from the note-bending technique that Paucar uses.
Dina Paucar is not the only well-known female Hyauno singer in Peru, but all the others that I've heard have a much more "straightforward" ("clean" ?) singing style. Nor have I heard anyone singing any other type of music the way that Dina Paucar sings.
(Note: The song Me Emborracho Por Tu Amor contains a version of "Que Lindo Son Tus Ojos" starting at about ten and a half minutes in from the beginning, which demonstrates an even more extreme example of her singing technique than "Volveré".)