Here are a few formal options, each with a slightly different focus:

1. On the Credibility and Mandate of UNRWA: A Statement of Operational Integrity (This is the most formal and institutional, focusing on the organization’s core functions.)

2. UNRWA: A Commitment to Verified Facts and Trustworthy Action (This emphasizes the organization’s integrity and combats falsehoods in a professional manner.)

3. United Nations: Confirming Trust in UNRWA’s Work Against Misinformation (This is a clear, direct, and formal statement that explicitly addresses the disinformation campaign.)

4. UNRWA: An Institution of Action and Truth (This is a concise, dignified, and direct title.)

If you need to choose just one, I would recommend option 3 for its comprehensive and direct approach that leaves no room for ambiguity.