slugs nesting in my dogs fur

Question
I have an American Eskimo, who loves to get dirty in our yard, and lay in all of my garden areas, and he most recently must have eaten something that didn't agree with him because he had the "runs", and was covered in poop that he rubbed into his fur.  I have bathed him twice, and tried to get the matting out to get it clean in his hind area, but couldn't get it all, so I tried cutting the fur, as well as using a "furminator", but his hind end was just way too sensitive.
After cleaning him in the shower the second time, my husband noticed two white slug-like creatures crawling on the ceiling!  I have been reading up on them, and I don't know if they have nested in the matting that i can't get out, and if they are dangerous to him?
What do you think?  Any cures?  Do I just need to take him to the groomer to have him shaved?  I hate to do it because of his double coat, but I fear I don't have an option?

Answer
Courtney-

I fear what you are describing is maggots that have nested in your dogs matted fur- this is a serious condition indicating a very bad skin condition under the mat. He needs to be taken to a vet and be shaved down immediately.

I hope he feels better!