I mis-read your original post -- thought you were in Minnesota rather than New Jersey. If you're in New Jersey, I can almost guarantee you do not need to worry about introducing Eisenia fetida as an invasive species. In an area so heavily populated an human-impacted as NJ, I'm sure that Eisenia fetida is already there.

While there may be nearly untouched wilderness in northern Minnesota where Eisenia fetida is not currently present, I'd be extremely surprised if there are suitable areas in New Jersey where the species is not already established.

I agree with someone else's suggestion if you need to prove this to superiors. put down a pile of horse manure in a shady spot, and just let it sit for a month or so. If you dig it up and find Eisenia fetida, then there's no concern about introducing them to your area.