Judging by some of the old patents he's filed [1], I'd guess he has at least a decent understanding of the tech involved. Probably less so, when it comes to the details of more modern distributed systems, but I also wouldn't be surprised if he's spent some effort towards all that as well - he's been working in/around pretty cutting edge tech for quite a while. Could he sit down and code it himself? probably not, but that's hardly required in his situation.
1. https://patents.justia.com/inventor/elon-musk