Hi Brian,
I think your best bet is to use JSON Structures in combination with Export Mappings. This will allow you to take your Mendix objects, pass it through a defined JSON Structure using the Export Mappings, then have your data in a nice JSON string that you can pass to AnyChart as a data feed.
You don’t need to set up a REST service, but JSON structures and Export Mappings are two of the key tools Mendix uses in that process.