Anyone with sufficient knowledge of algorithms and networking should be able to understand how it works without reading the code.
And there should not be "the" code, since the maintainers of that code would be a central authority.
Is there a reason to explain C++ code in any other [human or computer] language?
Of course. Machine verification. It could be even a subset of C++ like SystemC. But the proper definition of consensus-critical portion should be machine-verifiable.
I'm pretty sure that at least gmaxwell understands the importance of that. He's an advocate of zk-SNARKs and those have a synthesis of logic circuit equivalent to the given program as one of the intermediate steps.
The zk-SNARK people in Israel designed and implemented some subset of C (not C++) to facilitate logic synthesis. It is a key step to machine verification of the code.