What Disney does doesn't really matter that much anyway. There were (and almost certainly would be) numerous parties pushing for copyright extension and only mild opposition in Congress or even, for the most part, outside of it. This was, after all, before the Internet really took off, and especially before user-created works really took off and many people had interactions with the copyright system and started to detest it. In the 1990s, infringement would mostly have been about relatively large and obviously criminal or at least exploitative operations, hence it was easier to get support for an extension of terms. So the timing might be altered, but an extension to European terms is very likely to happen.