Welcome
@NipplelessWoman, it's so exciting to have you here, you've been a blessing to us. Parroting everyone in agreeing that Strokey the Snowflake is fucking amazing!
The story behind it is Mormons believe there are certain spirits who are too special to be tempted, so they're given disabilities like cerebral palsy, Down syndrome, autism (for the most part, it's more-or-less for the severe end of it) and other maladies to protect them from Satan and his angels. So I get why everyone in his class was saying that, but unfortunately for them, they don't/didn't realize Moebius syndrome doesn't necessarily mean those afflicted can get a free pass into heaven. All it does is affect their facial muscles, not their
mentality (and thus if they can determine good and evil and (I think consciously?) make their own choices and judgement on them), and thus Russ is fully aware of the choices he's making.
So if I could throw in my hat into the collective theory ring, my guess is Russell was a fence-sitter in the pre-existence. Someone
really wanted Russell to stay, and managed to talk him into it. Who that saint of a spirit was, we can only guess at this point, but it's probably pointless to do so.