Awkward question.
I guess this is a question that only the 'social' media platforms would be able to answer: I wonder what adverts were being shown around the original and subsequent copy videos and pictures of the crime - and what the owners think of their adverts being shown in that context. If I were an advertising customer I would want to know. A vain hope, I fear; I expect the platforms would strongly resist publishing those stats.
The multi-layer contracts selling screen space probably preclude the advertisers (the platforms' actual customers) suing the platforms but if we (Joe Public) could be told that (say) XYZ company's adverts were shown to 10% of people who viewed the crime then XYZ's directors might be interested in reputation damage limitation and bring additional pressure to bear.