Leather interiors in most cars have a protective top coat which is closer to plastic than leather, I don't know if house hold furnature is the same. I find that a steam cleaner & microfibre cloth removes almost anything from lether interiors. I very rarely use dedicated leather cleaners, I work through a trial and error system to remove stuff from leather.
1. APC (10:1) + leather brush (it's stiffer than a shoe polish brush and less stiff that a nail brush but either of those will be fine)
2. Steam cleaner & microfibre cloth
3. Spray with APC (4:1), agitate and steam clean.
4. Gilptone leather cleaner (the strong one, I haven't got the bottle at the house to check the name) & steam clean.
Failing that you'll have to think outside the box. Turn the sofa over and test white spirit and thinners on an unseen area, apply them to a cloth and rub onto the surface rather than pour it on but that's common sense really.