I suspect you are both right. It’s more of an issue of cause and effect. I have dealt with this scourge in a large field here in Arizona a few years back. We had an invasion of caterpillars which consumed some of the exterior foliage but ultimately made their way into the center of some rather dense colas. The caterpillars were basically living in a buffet. As the caterpillars made their way to the interior of the buds, they defecated along the way. The combination of the bacteria from the caterpillar feces and the moisture from the buds made the conditions perfect for botrytis (bud rot) to develop. We lost a lot of that crop.