Rationality conjecture for residues of 2-flags of holomorphic foliations

Let $\mathcal{F}=(\mathcal{F}_{1},\mathcal{F}_{2})$ be a 2-flag of holomorphic foliations on a complex manifold $M$. Let $S$ be a compact connected component of the singular set of the flag, and let $\varphi=(\varphi_{1},\varphi_{2})$, where each $\varphi_i$ is a homogeneous symmetric polynomial of degree $d_i$ satisfying the referenced condition.

Rationality conjecture. If the polynomials $\varphi_i$ have rational coefficients, then

$$\operatorname{Res}_{\varphi_{1},\varphi_{2}}(\mathcal{F},\mathcal{N}_{\mathcal{F}},S)\in H_{2n-2(d_{1}+d_{2})}(S;\mathbb{Q}).$$

The claim asserts that residues associated with rational characteristic polynomials define homology classes with rational coefficients. The supplied text does not indicate whether this result is proved or remains open.