Despite the best efforts of Backstage, the guy figured out I was the one to rat him out. He needs to quit while he's behind:
I heard you did not like my comments (see below): I am sorry, and I hereby withdraw my comments.
I liked your work and am interested in meeting at a future interview with hope to work with you.
And, as a well-wisher of you I suggested 'losing weight' is a good idea as if you are my daughter—by the way, I am from India.
I am so sorry to make that suggestion.
Mostly this makes me sad that he would talk to his (hypothetical?) daughter like that.
Time to contact the casting website again! They won't be able to do anything since he contacted me personally (his account was suspended), but they should know this in case they decide to reconsider.