Via code inspection, I believe that the span here:

https://github.com/10gen/mongo/blob/3a49a0db4e130569fcd57f735a4c637499bfe3cb/src/mongo/db/s/resharding/resharding_coordinator.inl#L794

only waits for the callback to return the future and doesn't actually wait for the completion to finish. We should try fixing other patterns like this as well.

It looks like a most of the spans in ReshardingCoordinator::_runUntilReadyToCommit have the same pattern