We have worked in Colombia at a foundation called "Forjar" with abandoned children who have cancer. In fact, the first recorded case of EMDR with phantom limb pain came from that group. Clinical reports on the use of EMDR with battered women have been extremely positive.
While there have been no studies focusing exclusively on domestic violence or homeless populations there are probably some treated in the larger EMDR PTSD studies which used mixed samples. You might want to look at the studies by Marcus et al. (1997); Scheck et al. (1998); Wilson et al., (1995, 1997).
If you like, I could forward your request to the EMDR discussion list if you wish to speak to clinicians working with these population.