Maybe they did a drug screen or a physical and they failed one or the other. They probably had to "sign" them with a clause stipulating they had to pass medicals and all background checks, just like in a normal civilian new job hire (except most new jobs don't require a physical...at least not the ones I've been involved with).
IDK about that '67...would think a failed drug screen would mean NFL involvement and some type of announcement. Same for a medical....I mean, not as if teams don't announce when Player X fails a physical for whatever reason.
Maybe Gruden worked them out and didn't like what he saw....just doesn't make for good optics for the team, given all the other questionable decisions by the team that have made headlines.
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