It seems like a great idea in principle to snag an extra pick. The issues I see though are;
1) Fowler has to sign the tender to tradeable, so he controls were he's going sort off.
2) If he signs the tender, our own cap takes an instant hit of around $17-18m. If we're unable to then trade him, it's guaranteed at signing I think. If we are able to trade him and reclaim that cap space, until we do, we won't have much money to sign other FA.
So if Snead can pull off a tag n trade to somehow gain a 2nd or more, that might be worth the trouble rather than just hopefully getting a late 3rd next year!