Do you find out the way to fix this issue? I met problem with the same Sitefinity version
Go to News Settings -> News -> Controls -> NewsBackend -> View -> NewsBackendEdit -> Sections -> MoreOptionsSection -> Fields
Choose 1 of 3 fields:
When I clicked Save changes button, a lot of choice items were added to ChoicesConfig (See attachment). Then I changed the RenderChoiceAs of 3 above fields to DropDown and the error gone. It happens to blog post, news, event...