Well, the main free agent signing period unofficially ended at the owners meetings. It's true that he could have been signed any time since then, but after the owner's meetings, most teams shift their focus from free agents to the draft. After the draft, the average dollars associated with veteran free agent contracts goes down, so it's probable that nobody will sign Gold until after April 25th.
Why hasn't anybody signed Ian Gold yet? Last year he was one of the best LBers before his injury, he's young, sure he could miss the preseason with that injury but the long term benifits are great! He's fast, strong and a hard hitter, exactly what we need. He reminds me of Matt Blair, We need this guy!