Yue's critical exponent gap conjecture for complex hyperbolic Kleinian groups

Let $m$ be a positive integer, let $\mathbf{H}_{\mathbb{C}}^{m}$ be complex hyperbolic $m$-space, and let $\Gamma$ be a convex cocompact isometry group of $\mathbf{H}_{\mathbb{C}}^{m}$. The critical exponent of $\Gamma$ is denoted by $\delta_{\Gamma}$. Yue's conjecture. Suppose that $\Gamma$ is a convex cocompact isometry group of $\mathbf{H}_{\mathbb{C}}^{m}$. Then either $\Gamma$ is a uniform lattice, in which case $\delta_{\Gamma}=2m$, or

$$\delta_{\Gamma}\leq 2m-1.$$

The conjecture proposes a gap below the maximal critical exponent for convex cocompact groups that are not uniform lattices. The result discussed in the source produces counterexamples to an analogous gap in dimensions $m=2$ and $3$ for finitely generated discrete groups, but the supplied text does not establish whether Yue's stated convex cocompact conjecture itself is resolved.