A:Answer Not sure what you mean by the player has a three prong RCA input. RCA input should have two jacks, normally red and white. Also your DVD should have two RCA output jacks not input. The stereo will have two RCA input jacks that these connect to. This kit should work fine but I'd suggest you get two RCA splitters aka "Y". Plug the two male rca's one red from DVD and red from this kit into one and that into the stereo and do the same for the white. Just don't have both devices playing at the same time. I don't see why this shouldn't work.
Good luck,
Jeff