Can you hold him in your lap while holding a wet towel on the wound? Doing this might help loosen stuff up.
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That would work if he's not too waterproof. If too waterproof, the wound on his back won't get wet.What about letting him soak in some nice warm water? or would getting him wet not be a good idea?
Can you hold him in your lap while holding a wet towel on the wound? Doing this might help loosen stuff up.