I don't know if anyone has solved your problem about the YAMOMAMI/WAICA
"tribes" yet, but here you are:
According to Dr. Aryon Rodrigues (LINGUAS BRASILEIRAS - Para o Conheci-
mento das Linguas Indigenas. Sao Paulo, Edicoes Loyola, 1986), the term
"Waica" is one of the names given to the YANOMAMI linguistic family, which
includes the following languages: (a) NINAM or YANAM, spoken on the Mucaji
and Uraricaa Rivers; (b) SANUMA, on the Uraricuera and Auaris Rivers; (c)
YANOMAMI, YANOMAME or YANOMAM, on the higher course of Catrimani and Mucajai
Rivers; on the Uraricuera, above the SANUMA, and on tributaries of the Negro
River, as the Demini, Araca, Padauari, Marauia and Cauaburi Rivers; and (d)
YANOMAM or YAINOMA, to the East and South-East of the area (which includes
the States of Roraima and Amazo- nas, in Brazil, and the Southern region of
Venezuela), on the Catrimani, Ajarani and Apiau Rivers, to the North up to
the higher course of the Parima River.
Besides WAIKA/WAICA, other names are given the YANOMAMI linguistic family.
They are: XIRIANA, YANOAMA and YANOMAMA. YANOMAMI is the more recent term; I
mean, it has been used more frequently nowadays for designating this
linguistic family.
References may be found in Rodrigues' book.
I hope this may have helped you.
Good night,
Chris.