It appears that a binary of GV is not available for CentOS 7 that provides json output. Is that correct? Would it take a compilation of source to achieve this?
Not exactly sure what you mean that a binary like this is not available. Installers including for CentOS 7 are provided for each release on Gitlab. These are built via a process that involves running the test suite that includes tests that use the json target. So we have reasonable confidence these support json. Do these not work?
If you’re getting Graphviz via the default CentOS 7 repositories, you’re getting a very old version, 2.30.1. This was prior the json target being added.