Hello,
I am sorry you were in an accident & I hope you are ok.
However, your dragon may die if you can't get him any medical care, too which is important. He could get an infection from the bites. His arm literally fell off? What does his tail look like?
It is likely that he is getting an infection if he is already lethargic & not eating. Can you post a picture of him so we can see the severity of his injuries? You will need to keep those areas clean with some diluted betadine & antibiotic ointment on it at least 1-2 times per day. Though this will help it will not take any infection away that could already be present internally or traveling up his tail.
If you cannot afford to get him cared for properly, perhaps it might be a good idea to contact a rescue facility to see if you can get him to someone who can provide him with medical care right now. I realize that is not an easy decision, but, he may not make it if his injuries are that severe & not treated. He will most likely need a partial tail amputation from this.
On another note, you can never house 2 males together, it always ends in trauma one way or another.
Please keep us posted on him.
Tracie