Comparison conjecture for the Maulik–Okounkov and cuspidal quiver Lie algebras

Let $Q$ be a quiver. Let $\mathbf{g}_Q$ be the $\mathbb{Z}$-graded Borcherds Lie algebra constructed from stable envelopes in Nakajima quiver varieties, and let $\widetilde{\mathfrak{g}}_Q$ be the $\mathbb{Z}$-graded Borcherds--Kac--Moody algebra associated with the graded Cartan matrix defined using the polynomials $C^{abs}_{Q,\mathbf{d}}$.

Comparison conjecture. The $\mathbb{Z}$-graded Lie algebras $\mathbf{g}_Q$ and $\widetilde{\mathfrak{g}}_Q$ are isomorphic.

The source describes this as essentially a restatement of Okounkov's character conjecture. It is conditional in motivation on the positivity conjecture, and no proof or disproof is supplied.