I don't think so. The plan was not to move the entirety of WDI. Like you said they use this building for tours and essentially as an archive these days. Some will stay and keep this as their home. Many will move as well.
They can keep the building and still move WDI. You don't have to be an imagineer in order to give a tour of 1401.
If they keep ANY part of WDI in the building, they will still be bifurcating teams. If the executive leadership (Weis/Bouza/et al) stay in Glendale, and ship the lower level folks out to Florida, that new campus won't solve any of the communication problems they laid out as their reasoning for moving. Certainly, if a team stays behind in California, that team will just keep growing and growing overtime as the "real" WDI while the team in Florida languishes.
I'm starting to fall into the camp of thinking this was a layoff/reduction disguised as a relocation effort.