The other other other other other clone - 100% Hitachi, of course, with an HLK T-tag, previsibly, where "H" is Hitachi.
Considering Denon's long time involvement in PCM, this rebadge was a strange marketing move.
I was told that Denon supported a homebrew variant of CD (like Victor, Telefunken or Pioneer) so this may explain that...
However, unlike Sony, as Denon invloved in PCM since 1970, Denon never envisioned PCM as a mass-market consumer format : it was mostly a way for the pros to better record and master but not something that would, ultimately, put LP replay aside and be used by Mr and Mrs Everybody.
Sony thought differently... and made CD with Philips.
Denon's 1981/82 prototypes were far more original and interesting, especially the last one.
But this first physically vertical but market-wise low-profile player didn't stop Denon from being successful with most of its own CD players throughout the following couple of decades !
All about the DCD-2000 at the indispensable vintage-audio-laser.com.