Here's another link that describes the other controversy in Afghanistan that Frank Kearney was involved in with the Marines Special Op guys. It has a pretty good background of what's alleged in that case.
Web site to raise support for MarSOC Marines
Your link to Gen. Patreaus' letter is interesting. It may have some impact on Kearney's actions. In this current case, the alleged incident happened in Oct. 13, 2006. Haditha and Hamdania cases may also have played a part to try to get ahead of the "stink" that media and local insurgents can bring to bear. This case with Anderson and Staffel doesn't pass the smell test of a crime by any means, IMO. Here's another link to this current case
On Special Forces, Snipers and the ROE's.
How's the nephew doing?