A TIA (transient Ischemic Attack) is temporary and completely reverses itself so it doesn't sound like he had a TIA.
An ischemic stroke means that blood was blocked from part of the brain long enough to damage brain cells. For your brain to recover it needs to create new paths and find new ways to take over for the damaged area of the brain thats why recovery can be a long road and you never actually know how much recovery is going to take place or when it will stop.
I wish you the best of luck and a recovery for you husband