I'm not totally disagreeing with you, but I'm not sure that messages being sent at this point is as important as seeing as many players as you can. Chan isn't being evaluated. Maybe us fans are, but it's not his job to try and impress us (now). It's to evaluate. That's priority one right now. In saying that, challenging that play and having the Redskins either score on the next play or kick the field goal does little for the long term. If this team is fragile enough to get down on a decision like that, we are in serious trouble.
Let Chan do his thing man, he's an NFL coach. We aren't. You've got to take things like that with a grain of salt.