The Chachamim relied on Todos ha'Rofeh, but there doesn't seem to be proof that he was Jewish. Rav Halperin, however, in Atlas Etz Chayim, has an entry for Todos and says that there is no proof that he was a Talmid Chacham but only an expert doctor; this implies that he assumes that Todos was Jewish.

There is another Todos -- "Todos Ish Romi" about whom Rashi says explicitly that he was Jewish (Pesachim 53a).

In the Tosefta in Ohalos, he is called "Teodris the doctor."

All the best,

Reuven Weiner