Well, it's the definition as such. Under Eu OPS visual approach is still part of IFR clearance thus published missed applies unless of course ATC instructs you otherwise. Under FAR it was quoted before visual isn't part of IFR any more. That's the whole difference.
Neither assertion is correct, 9.G. A visual approach is an IFR approach under both FAA and EU OPS rules, and indeed under ICAO rules (PANS-ATM 6.5.3). But since an IAP may not even have been included in the clearance, there may be no "published missed approach" to fly in any jurisdiction. There may even be no IAP for the runway in question. If you can find something in EU OPS to the contrary, then cite it.