I hc that Gerspard, Da Da and Scoper Master (the spark) run a scam as “therapists”
And basically that’s how he got the details for the painting of at Aguie and Woodrow. (He might have done an honest interview with Bea and Momma.)
Also when it comes to Orion he just asked why he was trying to get into the palace and after he hears all what happened to Orion he just pushed him aside and placed all the paintings in the palace without caring about any darkmess or Midnite.
Gerspard is such a minor character, but with such an important role to make us understand the lore I'm surprised he wasn't more fleshed out in the game.
Him being a fraud (or at least a very eccentric artist with equally confusing creations) is not that far fetched of a theory: Dada was an art movement which basically said: "Dada means nothing, everything can be art" (Confused? Well everyone was, lol). Even Gerspard's interpretations of the Wardens' backstories.