Just an opinion here, but remember these cels are 
from a sequence and just because one has one 
shadow on it does not mean the next cel in the 
sequence will have that exact shadowing. In 
addition, in regards to color, unless you are 
looking at the cel directly, a scan is not really 
that useful for deturmining authenticity by color. 
Most scanners will not get the color perfectly 
correct. I use a $1100 graphic art scanner when I 
scan my cels and it still messes up the purples 
and pinks and bleeds out the color slightly. I 
usually have to correct manually in photoshop to 
fix these problem. Maybe other people are more 
skilled with a scanner and always get the colors 
exactly right on the first scan, but I have a 
feeling that this ability is not that common and 
unless you are willing to put in a bit of effort 
most cels will be color and sometime contrast off.
This could easily be a case of that.

My 2 cels,
Marcus

PS  If you do not buy the cel, feel free to send 
me the info on the cel. I probably would be 
willing to get it.