Idu-Taraon is definitely a Sino-Tibetan branch, although likely influenced by Greater Siangic, which could be an ancient linguistic area or perhaps even an separate language phylum altogether.
Similarities are shared with Nungish, rGyalrongic, Hruso-Miji, and Kho-Bwa, pointing to Idu-Taraon as being part of a wider linkage of Eastern Sino-Tibetan languages.
Layers
Eastern Sino-Tibetan independent branch
Greater Siangic
Sources
Bruhn, Daniel; Lowe, John; Mortensen, David; Yu, Dominic (2015). Sino-Tibetan Etymological Dictionary and Thesaurus Database Software. Software, UC Berkeley Dash. doi:10.6078/D1159Q
List of reconstructions (Hsiu 2019)