A completely “clean” center channel is rare. It’s normal for it to have some music, mixed at a lower volume.
What can happen is the opposite, where the L,R and Surround channels are completely free of dialog.
Unfortunately for EP2 you have some very low dialog there…
My advice is to split your audio to two tracks: dialog and music
You can edit each differently, cutting at different points, to make it seamless.
Usually you cute music less of course.