I think so - I can't find any evidence of a genetic link, and there is one case report of them occuring in the same patient. That case report includes notes that there isn't necessarily a link, but that although gastrointestinal issues are common in NF1, coeliac should still be considered as a coincidental diagnosis.

The only real link (or 'link') I can think of is that kids with NF are more likely to have plenty of paediatrician contact, which might mean that CD (which flies under the radar a lot) is more likely to be diagnosed if present.