Monkey the Rescue Dog needs help!

Four years ago I was handed a rescued dog in desperate need.  He was so malnourished he looked like a little blackrat.  He had been born and 'raised' locked in a closet for months with his siblings and mother by a disturbed woman, who killed his brother for making too much noise.  He had never been outside, didnt recognize any food, treats or meat I put in front of him and remained dead silent for two months after I had him.  The first 3 weeks he lived under a suitcase in my closet beforefinally trusting me enough to poke his head around the corner.  Years of love and he has become close to normal, and the sweetest, most loving dog ever.  His black fur turned brindle with nourishment and until last week he was happy and healthy.  

He is now struggling to survive and still undiagnosed.  He can't eat, is vomiting and will soon starve to death.  We ran a gauntlet of tests and have reached the limit of what we can afford to keep going forward.  The next step is a $3000 endoscopy to explore a suspiscious area in his colon in the MRI/xrays, and then possibly a biopsy or surgery.  My heart is breaking at the thought of our poor sweet Monkey starving to death or being put down, when he has only given SO much love, and who has had so much suffering already.  Any thing is helpful, any contact or veterinary sponsor or help... but ASAP, as he is just wasting away in front of us.  Funds will go 100% to his medical expenses and diagnostic costs.  Thank you.  Here are a few short moments showing this beautiful little soul...