I guess the wrench that could be thrown in is the use of the Enterprise-C footage to depict USS Excalibur in the episode "Redemption". Granted, it's a fuzzy little shot, but at least in theory we do see this starship, associated in dialogue with this specific name and thus in Okudagrams with a 26000-range registry, sport the telltale "first batch" ramscoops.
It's true they used stock footage of the Enterprise
-C in one shot, but the footage of the Excalibur
actually shot for the episode, namely the wide shot of the fleet, clearly shows her to be of the later variant type.