I think any that do, are a coincidence. The text is meaningless. The one that was just revealed as the Zoat for example just had this text:
‘Behold the Rumour Engine! Can you predict what it is?’
Or this, from Vorkmortens coffin:
’With a crash of thunder and a flash of light, the Rumour Engine sends another image back through the vortex of time! Can you decipher this glimpse of the future?’
Most of them are just vague references to the engine itself or seeing the future.