I don't think iruma realizes the extent of Beem's madness induced painting, he's new to the world remember? and like the real world, people don't put too much into learning art history (or art in general) like artists.
the outcome of this chapter was predictable considering everyone was too hands off with beem, it's obvious that it won't be allowed to used, but what I like is that we're shown she's actually considerate enough for Sylvia('s sanity) maybe in response to her feelings.
i feel like the solution here is that they have to make a copy of the original, which lessens the madness inducing effect, considering sylvia was fine after seeing a copy of the painting as a child.