Jews were never referred to as Palestinians. Palestine was exclusively a Christian land from 380 AD until the Muslim conquest. Chronolgy is a *****.
Of course Jews in Europe were referred to as 'Palestinians among us',
2 centuries before Arabs decided to use that name. I've already provided the evidence.
If what You say about Jews in Palestine was true then Jews would lack many great works like the Jerusalem Talmud (aka 'Palestinian Talmud'), that are in the heart of their tradition.
But somehow amazingly there were significant Jewish schools that compiled huge volumes of works during the time You were talking about.
Jews were referred to as 'Palestinians' in literature and by law (something I've learned from Tinmore).