Exactly so; the NDB is the bit on the ground and the ADF is the bit in the aircraft.
2 parts of the same system; the ADF will point to the NDB. And that's it, at least for us KISS adherents.
As I understand the remark about a "back-bearing", an ADF will not show exactly that. What the pilot must do is subtract 180 (using a calculator if necessary) and fly the reciprocal, not forgetting to adjust for drift, so that the bearing to the NDB remains constant as he flies away from it. Or something like that. It's been a long time...... as I recall it, some mental agility is needed when you are doing this in IMC as part of an NDB approach/cloudbreak, what with everything else to think about.