It looks like an official announcement from Korg to me. Not really any reason to be skeptical here...
When ARP went under, they sold a lot of their assets to Fender, which was then owned by CBS. The Rhodes Chroma was actually an ARP design that hadn't made it into production yet. The ARP 16-voice piano which did get out the door at the very end was also sold under the Rhodes name.
The current Fender company was spun off by CBS and the Rhodes brand ended up being sold to Roland
So I'm sure just trying to figure out who owns the rights to the ARP name and designs required quite a few lawyers.
It's certainly unusual that Korg would choose to reissue a competitor's instrument rather than one of their own, but the Odyssey is a great choice. Throughout the 70s it ran neck and neck with the Mini as the
monosynth to own. It's fallen in regard a bit since then but it has a lot of very cool features...cycling EGs, a real
sample and hold (not just a S&H wave for the LFO), hard sync and ring mod (both absent from most Moogs).
The prototype photo sadly shows two of it's weakest points...the PPC control (pressure sensitive bender) and the keyboard overhang. Oh well, if you change anything
people will bitch.
I listened to Hatfield and the North at Rainbow. They were very wonderful and they made my heart a prisoner.