You might not care but it's relevant. It establishes the pattern. The greater the number of jews the thicker the conspiracy to blaspheme and slander Jesus.

If she were not Jewish, it would add weight to the argument that the artistic director was the only jew involved and be more of a coincidence.

1 jew is an individual doing something. Now we've confirmed that the star parodying Jesus in the last supper is also a jew. Put in place by the other.