Equivalence conjecture for regular relational symplectic groupoids

Let $M$ be a (possibly non-integrable) Poisson manifold. A regular relational symplectic groupoid integrating $M$ is a relational symplectic groupoid of the regular kind used in the paper.

Equivalence conjecture. Any two regular relational symplectic groupoids integrating $M$ are equivalent.

For integrable Poisson manifolds, the paper establishes equivalence with every $s$-fiber connected symplectic-groupoid integration; the conjecture extends this comparison to arbitrary, possibly non-integrable Poisson manifolds and regular relational symplectic groupoids.