As I think you know, the CoCC book doesn’t go into much detail regarding the earlier bombardment, most of it concerns the Clovis mass extinctions for which they’ve gathered so much evidence. I can’t recall offhand (and I’m not a great housekeeper, so I can’t prove that the book is or isn’t here right now) what the first bombardment was made of, but it must have been faster-moving, probably lighter but more energetic particles.
Why is it that overactivity in the mind area is so often correlated with underactitivy in the housekeeping area? I can’t find my copy either.