[philman_36]

So he is an MI hold which means?
Well, it's in the report that you're citing. Did you miss it? Edit-Find-"MI"...Military Intelligence.
But back to the dog bite. There is no way that we can know at this point that this particular person pictured was the one bitten.
There is also the possibility that the "detainee" was bitten in one of the numerous riots or attacks on the MPs.
Even "a nip" can be pretty serious if it is in the right spot.

[IfYouSaySo]

Is an MI hold a relative you think might know where his brother is? MI hold can include alot off stuff. And, like you said, a dog bite may be minor.