The more I'm thinking about this, the more it makes sense that there is some money/cap ramifications at play with the confusion. It reminds me of when Edelman got cut, and people were PISSED, thinking the Pats screwed him or disrespected him by cutting him before he retired. But then it turned out there was some benefit he was eligible for that he wouldn't have been if he'd retired under contract (I'm fuzzy on the details now).
This could be a case of it being beneficial for Tom or the Bucs or both if it's not official until a certain date. Or he could be legitimately still mulling it, but the former makes more sense to me than some (usually) very professional reporters went all in on a story that turned out to be horse cabbage.