In conflict resolution it is important we redirect all employees to the party they have a concern. We know that it might not be adviseable in all cases to recommend this with two parties that are not emotioanally ready to confront another employee with issues. In those cases it is best to gather as much of the facts as you can and then interview each party. Communication is 7% verbal, 13% body language and 80% listening. The listening part is where you can best evaluate and analyze the issues. When you have been a good listener to all stakeholders you can enhance your potential for resolution to the issues. Point out each person's strengths and do not highlight weaknesses. I know you had mentioned the potential of having the parties meet together which is a good idea but you may have to be involved with the meeting if necessary.