Different side of the coin, I think this looks bad for us. Notice how Chris Brown's message made sure to include the terms "standard procedure", ie nothing special. If things were truly in the imminent contract signing stage, he wouldn't have posted anything and instead waited for Williams to sign and THEN break the news.
Nix is probably shaking Mario's hand, telling him the Bills will be here with their offer and wishing him the best in his future visits.
Mario leaves and never comes back.