The ball is in your court. Put your group of two hundred victims / carers / whatever together and things will start moving. That said, its not sufficient to merely claim you have the numbers, you need to have them readily available and ideally accessible for interview before any lawyer will take you seriously. Lawyers are too busy doing stuff they know will make them money that to be bothered following up lost causes. I've used a particular individual I've found effective in matters involving the bureaucracy, he's OK with class actions and doesn't necessarily view money as a God, but there is no way known he'll consider getting involved in a matter like this without ensuring beforehand that the two hundred you say you have are more than names in a phone book. That has been tried far too many times in the past for anyone to get caught again. I'm far from the greatest fan of lawyers and / or the legal profession but that said, I'm not prepared to alienate one of the extremely rare ones who is legitimate and is prepared to stick his nose into what is in reality a human rights issue with no relevant legislation by suggesting he take on something that potentially ends up with only one or two usable plaintiffs and tens of thousands of dollars in expenses .
Taking on Child Safety isn't like a class action against multi-zillion dollar international phamaceutical company, in particular it isn't likely to result in a significant payout regardless of how much damage has been done; the best you can hope for is a change of policies and hopefully a few bureaucrats shuffled from one ivory tower to another. Its not as if any lawyer would get excited about his 47.5% cut of a maybe $10,000 maybe nothing settlement. Like it or not (I don't, but then I don't make the rules), the commercial reality is there are costs involved and someone needs to pay them. Two hundred people by a thousand dollars each will buy quite a bit of legal practitioner time.
A lot of legal practitioner time equates to a lot of court appearance and given that children are sacred cows in our society, media attention is a given. I suspect that the media could well end up achieving much more than court processes although you'd need to court stuff to air the blood and guts that attracts media attention.