It's on Double-Headed Serpent by Inkuyo as "Callejon de Las Vinudas [Widow's Alley]" (with sound clip). "viudas" might be correct. I looked through Music of Bolivia - Llajta Musica!! and MUSIC from the ANDES...and nearby regions, but didn't find the music with that title (both are sites with a good number of recordings, though).

~Masato