References when my manager was laid off too - 6 months and counting

The company closed and I am not sure how to reach former colleagues. This is my first time dealing with any of this. HR only confirms titles and dates. Is a client acceptable?

Thanks for writing this out. I went through something close to it last year, and it settled down once I kept a simple log of every call and form.

I kept a note of my results so my references could be specific. They appreciated it.