This not easy to be answered especially as a lot infos remains (to me) unavailable due to being written either in russian or japanese font.
His Beethoven and Bach recordings issued on Denon were originally Melodiya releases .... but there are also broadcast recordings and I suspect Schumann Toccata op 7 + Fantasia op 17 recorded in 1970 is such a case ....
Based on the forementioned there had to be a licensing deal between Denon and Melodiya .... but remember, the Denon releases started in the mid90`s, when - based on the breakdown of Soviet Union - things were in "free flow" ....
But Anatoly Vedernikov was - due to stiff competiton from contemporaries -seemingly not considered premier line of Russian pianists, f.i he was not even granted a release within the highly acclaimed BMG/Melodiya 20 CD series "Russian Piano School" from 1996 ....
Nevertheless, if you can get your hands on any of his Beethoven or said Schumann Denon CD´s don`t hesitate ....