MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
Yeah, you will want to use the version of ArduinoJson mentioned in the Readme.md file. You have probably loaded the 6.X BETA version.
Remove the BETA version and load: ArduinoJson version 5.13.X.