Spoilers
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The curse doesn't seem to care whether you know its "rules" or not (Richard's memory of Sarah was jogged by reading the case file about her specifically). And the fact that it only affects one person at a time could give a (narrow but meaningful) advantage to an organization that keeps detailed records and already knows to watch out for something paranormal.
You could be right that Richard himself left the list behind of people who shouldn't read his files, though the fact that the organization (aside from Alan Thomas) knew to follow those instructions could still imply they'd figured out at least a little of how it works.
Richard's lack of connections was convenient, sure, but I'm wondering... maybe he wasn't always a recluse, maybe he was just the last one of his friends to get erased from the world's memories? The final note listed a lot of names on the chain in between Katherine and Richard, after all...