NEW DEVELOPMENT:
So I've still been messing with DOSBox trying to get it to read my CD's music, but this time instead of mounting my CD drive (E

as D, I mounted it as E
Mount E "E:\" -t cdrom
(instead of) Mount D "E:\" -t cdrom
When I ran the game, I checked the box for CD music in the preferences... Instead of having no effect like before, this time the midi music turned off and no music played at all instead. (The sounds still play normally.)
Does this change anything?