I could see this as being fake, but I believe it is equally likely to be real. 11th hour, slightly buzzed or worse, character is hanging by a thread and you want to stretch every rule to infinity and beyond? I have seen some ahem interesting...examples to "validate" a rules "extension". Chainmail belts, blowdarts, contained arson, to name the standouts. Just biting someone hard enough to need stitches? Easily possible.