“Verified as working on Kega Fusion 3.64, a Model 2 Genesis + Model 2 CD + launch 32X, a CDX + 32X, with a NeoFlash NeoMyth MD and the V1 Mega EverDrive, and also with Mega EverDrive Pro and MegaSD.”
And what it says on the Doomworld page: doomworld.com/…/119202-doom-32x-resurrection/“Selecting between no music, VGM FM music, or playing music from attached Sega CD (requires Sega CD in addition to 32X).”
It makes me think the game runs off the 32x cart and uses the Sega CD attachment to play the new music.