re: 12th Lithuanian Police Auxiliary Batallion

Emzed — I don’t think I can tell you anything you want to hear. The 12th Battalion were among the worst. If your grandfather was involved with them, then he at least watched things happening that no civilised person should see.
If you want more information, check out some articles on the Telegraph site ( Search for Antonas Gecas, aka Gecevicius. He was the commander of Platoon 3 of the 2nd Company of the 12th Battalion. They were all volunteers.
The Kurapaty Forest was nothing to do with them. In a way, your grandfather was right. More people were killed in Kurapaty than by the Nazis, if you want to judge these things by numbers. Sorry.