Are you selling it to them as a "finished" product, or would you consider it an ingredient in their finished product? (Note that if you're supplying the single product for their finished product, finish labeling requirements won't apply). You can't send it entirely unlabeled, but if you can qualify it as an ingredient sale then bulk labeling applies.
If they're applying retail/finish labels and assume responsibility for nutritional information and all the other requirements, you should be good to go. But keep the idea that if there's a recall, company might try and throw you under the bus (depending on the reason).
2.4.1.1 The site shall ensure that at the time of delivery to customers finished products shall comply with food safety legislation applicable in the country of manufacture and sale. This includes compliance with legislative requirements applicable to maximum residue limits, food safety, packaging, product description, net weights, nutritional, allergen, and additive labeling, labeling of identity preserved foods, any other criteria listed under food legislation, and to relevant established industry codes of practice.
2.7.2.1 The methods, responsibility, and criteria for identifying the site's vulnerability to food fraud, including susceptibility to raw material or ingredient substitution, finished product mislabeling, dilution, or counterfeiting, shall be documented, implemented, and maintained.