Yes DNA testing sure, however, many of the kids separated came with people who were not parents or relatives, children came with others who have left so it’s not as easy as matching up DNA with people that are somewhere here in the US. I agree the best way is to find out if any organization in your state is a contractor to the Office of Refugee Resettlement and see if they need any volunteers although most of the organizations don’t need volunteers unless they are licensed or approved as foster homes.Many of the organizations involved have been in various media articles. The kids are in multiple states (those that have been placed with foster homes)…here’s a local article from Maryland as an example:
http://www.baltimoresun.com/news/maryland/bs-md-separated-children-help-20180621-story.html
and one from Michigan:
https://www.metrotimes.com/news-hits/archives/2018/06/19/immigrant-children-ripped-from-families-land-in-michigan-heres-how-to-help
In my opinion, the best thing that can be one is to lobby the Congress to get their butts in their seats and work out some better immigration policy. This has been going on through multiple president for multiple decades and frankly I’ve been mad about it for decades. It is ridiculous to have laws that every president, Democrat or Republican, has either ignored or written executive orders to get around the laws that got written in 1997.