What about the narrower Campy chains? They (used to) make a different one to fit those.
No, they did not. Wipperman made a 6.1mm chain that they called "Campy compatible", back when Campy 10 chains were 6.1mm wide, and a narrower 5.9mm model that they called "Shimano compatible", but those chains and their connex links were never intended to fit any other brand of chain. Oddly enough, the link for the Campy model would actually fit a genuine Shimano chain and the link from Wipperman's "Shimano compatible" chain was not wide enough to provide the proper side clearance with a genuine Shimano chain. Confusing huh? Some people mistakenly bought the Shimano model (10S1) connex link to use with a Shimano chain and had failures since there was no side clearance.
Now Wipperman only makes the 5.9mm width and calls it "compatible with all 10 speed systems". The chain has the same dimensions as a KMC or Shimano chain. Both Campy and SRAM 10 chains are the same 5.9mm width as all others, but the width across the inner plates is narrower. Links that fit KMC, Wipperman or Shimano are a sloppy fit on a Campy or SRAM chain.