Novavax was tested against fetal cell line HEK-293
See here https://www.science.org/doi/10.1126/science.abe1502
and
So, it sounds like they used an insect cell line, but had a contractor compare their insect cell reaction to an aborted kidney cell reaction.
That might have been stated in the technical paper cited by lozier, but it was so technical I didn’t follow it. Or lozier has added a new link since last I checked. They had it rated both clear green and not clear red when I read it. (Just checked... they still do)