Hi, yes, never release aquarium animals into the wild as they can transfer disease and illnesses which the wild ones might not have.
It is very possible the babies will not survive. They need marine water for their larval stages.
I haven't read through all of this post but it looked pretty thorough.
FW & SW
Favorite tank right now - 72G Bowfront Wadai Tetra, Cardinal Tetras, Ghost Glass Cat Kryptopterus bicirrhis and Clown Loach Cory haven
New to FW fish? First tank in a long time or EVER??? Need some info on keeping fish?
Start here - Aquarium Advice Article