Yann Lecun's name is listed in the model card:
https://github.com/meta-llama/llama3/blob/main/MODEL_CARD.md
LeCun is head of FAIR (FaceBook AI Research), which is a different internal organization than the GenAI group responsible for these Llama LLMs.
"I had some input on our open source policy but I had no direct technical input on Llama-3"