Well, I know when the motor doesn't jostle about, then it means there isn't a good link between the mainboard and CD drive (often caused by a loose or disconnected ribbon cable, or disconnected power).
I note the modboard still didn't work. That sounds like the dreaded music CD error. It's usually the result of spontaneous failure of the board, though it will still connect enough of the data to access parts of the disc's data. Most likely, it's toast, if it is indeed a modboard.
As for the jumper configuration, it appears to be set for Japanese games, as according to Lawrence's chart
Also, what model of Saturn is this? Is it an American model, or perhaps a Sanyo? I believe the latter has an extra board inline of the CD ribbon cable, but isn't a modchip. Maybe that's the culprit?