After reviewing, we've decided to go ahead with the change since it seems to be the same just two ways of phrasing it. If the second was present tense I could see an argument to be made for "The comforter hurt them" vs. "The comforter is hurting them"

But in both cases the hurt is past tense and it's down to if it would be more correct to say "The comforter is the one who hurt them" they are the person who hurt them in the past. Or "The comforter was the one hurt them" to match them both to past tense, but that also sounds like they're not the same person who hurt them anymore. But either way the phrase means the same as "comforter caused the hurt".