The six constituent languages (Sobei, Bonggo, Tarpia, Kayupulau, Ormu, Tobati-Enggros) are each counted individually in the sources; no single family-wide total was found this pass, and no figure at all was located for Kayupulau.
What would resolve this A published survey giving comparable, similarly dated speaker figures for all six languages, including Kayupulau.
OpenAustronesian and Oceanic linguistics, New Guinea.Wikipedia: Sarmi-Jayapura Languages