I just did. And for the life of me, I seem to not be able to find it. No "it has been in-game since gamma" (and therefore no SRV needed to find it) official statement. Only some deductions here in the forum about the 2.0 patch notes that said "Secret added". Which may well have been just about the Zurara plot. What worries me is that allegedly DB said that it is possible to find Raxxla only "if you scan it enough". What does that mean? Do you have to be in a wing and do a simultaneous scan? Do you have to honk that system 100 times? That a FSS scan is enough? Do you have to do a detailed scan of each system body? Because some of these issues that I mentioned above make Raxxla nigh UNFINDABLE. Unless you already know what to look for from another source.
Someone explained to me once the difference between a code and a cypher. You may be able to crack a cypher because there is a certain logic and pattern to it. But a code is a basically a metaphor and therefore impossible to crack. IMHO Raxxla is a code.
I also believe that somehow by adding the FSS and the codex FDev wanted to make it easier to find, but the codex entry remains just another metaphor. Tiny bit obvious they think, but still, only a metaphor. There's obfuscation all over the place here, not just the outer rim.