In this second example of a restored slide with the same girl you can see the same problems inherent in the slide I encountered in the first slide. Slides are easy to restore because of the lack of grain (usually) and it's rare to get a lot of problems with slides. 

Here the problem was -  Do I give the girl priority in colour correcting or the background?. I concentrated on the girl's face and jeans which balanced out the colours. The wall was never going to be 100% accurate but it's very close. Maybe a shade whiter...

The yellow cast was simply caused by the fact that slide is meant to be used at a specific temperature which is based at a particular time of day the sun is out. Never happens. So colour casts are always going to be there.