Set AITA: reported a set to SAG-AFTRA even though I'm non-union

Was doing BG work on what turned out to be a SAG-AFTRA production (I was hired as non-union through a separate casting call — yes, this happens). On day 2, a practical effect went wrong and two background actors got minor burns. The production didn't file an incident report. They told us to "shake it off" and offered an extra $50 for the inconvenience. After wrap, I reported the incident to SAG-AFTRA's safety hotline even though I'm non-union myself. Some of the other BG actors said I overreacted and that I'll get "blacklisted." Did I do the right thing?