Interesting idea, I had never heard of the observation of a lunar impact before. It would be interesting to look for an unusual chemical signature in that dust layer (iirc Iridium in the KT boundary).

Now this statement makes me wonder how accurate the rest of his information is:

"It must also be considered that many of the major ice ages
were caused by orbiting dust from the moon, and that they will
also have left traces in the marine sediments. An examination
of the sediment samples would show whether the Ice Age which
began 15,000 years ago was also caused by an object impacting
on the moon. "