I’d guess that since the area is sceniced, the track is probably ballasted, too, so “freeing” it will have little effect. It is, however, a good technique for those who may have similar track issues and have not yet ballasted.
It’s still my feeling that the only way to correct this problem is to rip it out and rebuild it properly. Scenery is usually not that hard to replace or repair, and I think that it’s unwise to let that stand in the way of a proper repair. If necessary, tear it down right to- and including, the sub-roadbed.