As to whether or not it was a serious attempt to sell, I think it would probably be more correct to say, in business parlance, that they were "doing their due diligence" in perhaps considering an offer -- even if the offer or idea turned out to be a bad idea. (I think he was/is a major player in the Four Seasons resorts, and had major influence in the deal to sell the prime land on Bay Lake that became Golden Oak and Four Seasons. Not really sure of that, but I think you will find that to be true.)
But as for "due diligence," often companies' boards of directors will have to consider legitimate offers to purchase or buy out assets in order to show shareholders that they are giving due consideration of all possibilities, not just protecting management. I remembered thinking at that time that this was what they were doing -- considering a legitimate proposal, but that it would be demonstrated to be not in their best interest. The proposal can come from an outside offer, or it can come from internal sources that suggest that they should consider putting a unit up for sale.
Anyhow, I think reason prevailed -- in that they realized how integrated the parks and resorts are to their intellectual (entertainment) properties, and that it behooved them to maintain the control that comes with ownership, especially of such huge and iconic real estate and business properties. Any such sale, especially in Florida, would likely be more of a mess than they wanted to do. (I am sure that even the makeup of Reedy Creek Improvement District would be affected by a sale of the parks and resorts to someone other than the Walt Disney Company.) Perhaps a lot of lawyers would make money, but not so much the company.
The last paragraph was my own thought, but overall I think what really happened what just taking proper consideration of a proposal, however unlikely.