Idk anything about that type of worm but i know red wiggler compost worms avoid light and will always be beneath the top 1/2 inch or so, unless disturbed.

You bought the wrong worms. European Nightcrawlers will surface to eat but prefer deeper 10-12” depths. What you want for the top are Red Wigglers who prefer to remain in the top few inches.

European Nightcrawlers are composters too, although dwell deeper than Eisenia Fetida, but not as deep as the Canadian Night Crawlers. Nowadays, the composting worms of different species are often lumped and sold under the umbrella name of "Red Wigglers".