Undoubtedly not an Illegal BIB, but these are the toughest plays for any crew. No "standard mechanics" cover this so everyone's in a fire drill. Difficult to comply with the "see the whole play guideline" since if you did on this play it's clear that the blocker is out in front of, or maybe beside the defender when he makes contact. He was never behind him, which IMO supports the "we didn't see the whole play" problem.
We catch some part of the block (most likely the player going down part), make an assumption, and react with a "that looks like it must have been illegal" and throw. Have to see the whole play starting with prior to contact all the way thru the block, otherwise we need to keep it in our pocket. Also, as is the case here, the oft repeated "he landed face down so it must be a ...." just doesn't work here either.
