> My suggestion would be to rename a site "disaster indices" and include the waffle index as one index. Even batter (yes) if you add other similar indices, like theme park closures or other.
Is it really necessary to go that far though? I think they just need to stop using the visual mark and make clear that it's unofficial. (But I am very much not a lawyer.) You are allowed to identify a product or company by name so long as it's clear it's not you and trademark law can't be used to stop you (e.g., for a bad review). Maybe the site could be renamed "disaster index based on Waffle House closures" or simply "unofficial feed of Waffle House closures"