Where Cowher lands, he'll attract players. Free agents will WANT to play for him. Hypothetically speaking, they would likely plug the hole with Okoye or Robinson the first year, or package Okoye in a trade to a team with a 4-3 to find a stop-gap, until they landed their guy a season or two later.
As far as him going to Carolina, just because he LIVES in Carolina does not mean he'd want to coach there. That's just speculation. Texas is a 2-hour flight from Carolina. His youngest daughter is a senior now, and will be in college somewhere next year, so I don't think location is quite as crucial as it was when he resigned from the Steelers. He's going to want to go somewhere that has a good foundation and will be in the spotlight. Houston fits the foundation part of the bill way more than any other probable NFL franchises that will potentially have a vacancy. Cowher himself often comments on CBS about how good the Texans personnel foundation is. Fact is, though, Dallas is a more attractive option because of their media attention, and Jerruh would sell out to get Cowher like he did for Parcells.