
This is an interesting Weakness to rate. Looking at the two elements, the effect and the discard condition, we get:
The effect: Swapping the for the isn't fun, and it doubles you chance of auto failing, but... it's possible to go an entire scenario without seeing either token, so it's on the lower end of the punishment scale for signature weaknesses. It could even help you, if Daisy is running Voice of Ra, where the grants an extra 2 resources, while the is a miss. If you've had the bad luck to get Nihilism as your Weakness, you might feel differently. Still, not incredibly punishing.
The discard condition: 3 actions and 3 Horror, and the actions can be Daisy's bonus Tome actions. Daisy has a high Sanity, but this still eats a third of it. 2 actions to clear a Weakness is pretty standard, so 3 bonus actions is fairly forgiving, and Daisy can always pack Fearless (2) to recover from her unwise bedtime reading.
All in all, this is a below average signature weakness.