My brother is salty...

>asking a bunch of FGO players how to be okay with not rolling the the thing you want

Oh my sweet summer child

Actually I felt that also when I spent 200 sq for jalter and didn't come, neither a random 4 star servant. I think the only thing you can do is save the transfer number just in case. If his resentment of the game fade or come into acceptance after rerolling or so, well atleast his main account is save and he can come back to it anytime.

You don't. That isn't even a huge amount of quartz, if he gets so worked up over not getting what he wants then is better to quit this game since gacha isn't for him. with 0.7% of getting the rate up servant most often than not you won't get the servant you are after, you either accept that, became a space whale or quit the game.