Here are a few options for a formal title, depending on your preferred focus:
Option 1 (Direct and authoritative):
“Disinformation as a Strategy: Assessing Russian Accountability for the Strike on the Kyiv Pechersk Lavra”
Option 2 (Academic and precise):
“The Role of Strategic Disinformation in Obfuscating Responsibility for War Crimes: The Case of the Kyiv Pechersk Lavra”
Option 3 (Concise and journalistic):
“Weaponizing Denial: Russian Disinformation and the Strike on the Kyiv Pechersk Lavra”
Recommendation: Option 2 is the most formal and suitable for a report, article, or academic paper.