Week 5-recent conflict

In my classroom there are a total of three teachers and my recent conflict was with one of my co-workers in which her last day is next Friday she is leaving her position to move on to another job; which is great we don't have any problems with that. But last Monday i noticed that several of our Cd's and books and felt board games were missing because the children had been asking about them. I asked both of my co-teachers about the supplies and the one teacher who is leaving on Friday stated that she took the materials and they were in her car. So two of the strategies that i used was compromise and the 3r's; reciprocal, respect and responsible in which i asked the teacher to use her lesson planning time to either make duplicates of the materials again, so that the children would not be losing out or give all the materials back. I felt that compromising would help both sides give up a little and gain a little by having the teacher leave the classroom in which her help wasn't going to be needed for that hour but for that gain the children would get their materials back. I felt as though the 3 R's were appropriate in this case because the matter concerned more than two people and we must have respect for the classroom by not taking materials and responsible because someone has to be held responsible for their actions. What are your thoughts?