Well, I don't know what to do about her attitude towards you, but to help out your husband this book is excellent at dispelling the myths.
Of course I have never heard this particular myth. And this book is quite intense - but it does address exactly what are and are not risky situations.
I'm so sorry to hear that you experienced that. I went through some very similar things as a child. This book helped me a lot down the path of understanding and healing from some of my experiences, and I really strongly recommend it for anyone who has similar experiences: https://www.amazon.com/dp/1558741313/ref=cm_sw_r_cp_apa_ExtfzbZ171P4V
Have you talked to his case worker/social worker/treatment team about these concerns? They are going to be a better resource than reddit, I'm afraid.
There are certification classes you can take on therapeutic restraint and other tactics for handling rages and meltdowns - consider checking those out.
Is there a crisis team you could call? Check to see if your area, agency, county, etc. has support groups or other resources for foster families. There are often church-connected or nonprofit ones as well. It may feel like you are alone, but you are not!
Consider reading "Building the Bonds of Attachment" by David Hughes (https://www.amazon.com/Building-Bonds-Attachment-Awakening-Troubled/dp/0765704048/ref=sr_1_2?ie=UTF8&qid=1496171891&sr=8-2&keywords=building+the+bonds+of+attachment). It covers a really similar situation - a child who has violent and destructive rages as a result of trauma, and discusses therapeutic interventions (including holding). It looks like a really dry, dense, inaccessible book from the cover and title but it is actually really readable and really useful. Work by Karyn Purvis (http://empoweredtoconnect.org/) also has a lot of strategies for managing and healing this kind of behavior.
And, as always, document, document, document!
That's an awesome philosophy. I wish every workplace was like this.
I'm reading a book by Randall Fields that explains the struggles he had as a ward of the state, being black, and being with an abusive step parent.
This book has examples of not only Fields but people all around him that were affected by today's racism.
TL;DR: Racism today in the American work place (in NYC) does still exist.
Something like ten years ago, I happened across the blog of a woman living in her car. She was a great writer, so we, her regular readers, persuaded her to set up a PayPal donation button on the blog. That gave her enough of a boost to start renting a flat and eventually write and publish her story.