Type B area conjecture for q,t-Fuss-Catalan numbers

For $n\geq 1$, let $W_{B_n}$ be the reflection group of type $B_n$. A type $B$ Catalan path of length $n$ is a lattice path of $2n$ north and east steps from $(0,0)$ staying above the diagonal, and let $\operatorname{Cat}_{B_n}(q)$ be the sum of $q^{\operatorname{area}(\lambda)}$ over such paths. Type B area conjecture.

$$\operatorname{Cat}^{(1)}(W_{B_n},q,1)=\operatorname{Cat}_{B_n}(q).$$

The conjecture defines the proposed area interpretation of the $q,t$-Fuss-Catalan polynomial in type $B$ and is supported by the explicit calculations and path enumeration given in the paper. Its resolution is not specified in the supplied material.