Looks like they have been found alive and well.
Rainier is notoroious for weather, it can come in fast and nasty. The Muir snowfield can be in full whiteout conditions while a few thousand feet below at the parking lot it can be calm.
Also coming down in a whiteout is tricky, there are glaciers with dropoffs on both side and you can't follow the fall line because it leads to one of them.
A snowboarder rode to his death a few years ago trying to ride down in marginal conditions.
As far as rescue fees it is always talked about because all these rescues make the news and most of the public doesn't realize that the bulk of the rescuers are volunteers. Also the bulk of outdoor rescue money spent is not on these dramatic climber/boarder/adventurer types, but more on day hikers or kids who wander off a trail.