How do you capture a wizard?

[Malachei]

No, the Heavens have as many Solars and the Hells have Balors and Pit Fiends. The number in all cases is infinite. This are infinite planes. RAW there are an infinite number of Solars around.

Where exactly do the RAW give the number of Solars? Where exactly do the RAW state that the number of Solars is equal to the number of Balors and Pit Fiends?

There is only one Celestia. The rules say a plane is an infinite expanse, not that it has infinite Solars -- this is not the same. An infinite plane can be lifeless or the the home of just one creature.

And if the Deity wants a Solar back then he can have him back at the cost of a single Standard Action by simply using Alter Reality to fake a Gate spell and call the Solar back to him. It's easier for him to get his Solar back if he needs him at that exact minute than it is for him to kill you.

He is a lawful good deity, of course he cares about the solar. And solars are, by rules text, their closest attendants.