4 years later and still no resolution, except to open dataset in another project. Thanks esri!
Opened in another project and it still disappears when trying to edit. KUDOS esri !!!!
After pulling my hair out and a lot of cussing while waiting for esri "customer service" (and I use that term, lightly) to call me back, I have discovered it has something to do with setting the elevation of the multipatch feature to "On the ground". I turned off the WorldElevation3D/Terrain3D elevation surface mid-edit and the selected feature is visible.