Insect and Spider Identification: What bored into my pineapple sage?, 1 by dividedsky

dividedsky wrote:
The color might be off a bit because I didn't have enough light. It's fairly accurate, though, if I'm remembering correctly. You'll notice dark spots on the stripes, if the picture displays large enough.

I saw the white stuff first and thought it was eggs. Now I think it might be frass. I'm looking at the picture and seeing little brown things - hope they aren't eggs. Will soapy water kill caterpillar eggs, or do I need to remove, squish, or otherwise destroy them?