The verb form is where the atypical usage originates, so I think it's fair to focus on the verb as the point of interest despite including an example that happens to be a gerund.
Anyway, I think there's an even larger set that "spell" is a member of: metaphorical usage to highlight anything unwanted or erroneous; "code smell" is another.
It's wrong, therefore it smells. It's wrong, therefore it's misspelled. It's wrong, therefore it wants to be different (personification metaphor).
Yeah I have as well, I think it's both to be cute and to signify that they're equivalent."'IN GROUP' is an obsolete version of 'IN ROLE'" might mean that it was a subset of the latter with different behavior.