Jews that go caught pretending to be Christians, so they good stay in the area, were tortured and sometimes killed by Thomas of Torquemada on behest of the monarchy.
You are minimizing it by saying they “pretended to be Christians”. They agreed to be baptized and to live as Catholics, didn’t they? Knowing, presumably, what the penalties were for Catholics found guilty of heresy?
So blame Ferdinand and Isabella and blame Torquemada for their policies against the Jewish communities. Don’t blame the Inquisition as a whole, which was only doing its job as an internal watchdog of the faith.