Please do not use the oils as they can be aspirated into the lungs. You can try a little baby food prunes to see if it helps move what looks to be an impaction, but if it does not seem to clear, the Leo will need to see a Herp Vet. Some of the darkened areas can also be organs that you are seeing.
I would continue with the soaks and gently massage the abdomen from front to vent.
I would make sure the temps are anywhere in the range of 84-88*F in the warm area. The heat aids with digestion and may help get things moving.
If you need a Herp Vet, please supply a State and I can locate one for you. The Herp Vet may prescribe lactulose or parafin to help move the impaction. If bad enough the Vet may suggest surgical intervention. Joan
This is a link for the Herp Vets in Northern CA: http://www.anapsid.org/vets/califn.html
This one is recommended by other reptile keepers:
* Alex HermanAll Pets Hospital269 S Van Ness AveSan Francisco XXXXX-XXXX415-861-5725