"Exiled", when used as a state, means "in the exile zone", so the continuous effect created by Release to the Wind only last for as long as the card it exiled is in the exile zone. Since the commander never even entered the exile zone in this case, the continuous effect doesn't do anything at all.
611.2b Some continuous effects generated by the resolution of a spell or ability have durations worded “for as long as . . . .” If the “for as long as” duration never starts, or it ends before the moment the effect would first be applied, the effect does nothing. It doesn’t start and immediately stop again, and it doesn’t last forever.
If something did allow your commander to be cast from the command zone for an alternative cost, you would still have to pay the "commander tax" because the tax is an additional cost, and additional costs must still be payed when using an alternative cost instead of the mana cost.
total cost to cast
= mana cost or alternative cost
+ cost increases and additional costs
- cost decreases
The casting will also count towards the "commander tax" in future castings because the tax simply counts how many times it was cast from the command zone. For what cost it was cast is irrelevant.
903.8. A player may cast a commander he or she owns from the command zone. A commander cast from the command zone costs an additional {2} for each previous time the player casting it has cast it from the command zone that game.
I would take something that moves the commander out of the zone (such as Command Beacon) to avoid the the "commander tax".