For a definitive answer, go to FreshFromFlorida.com, search for “cottage foods” and download the PDF file they have there. In it, you will find a Tallahassee phone number you can call to get an official answer to your question.
Apart from that, if it is a powdered non-dairy creamer, the resulting glaze should probably be okay for cottage food. If it is a liquid, refrigerated non-dairy creamer, you’ll probably need to check with Tallahassee.
Either way, don’t forget to include all of the ingredients from the label of the creamer in the list of ingredients on your product’s label and, just in case, also include milk in the “contains” (i.e. allergen) part of your label.