Confocality conjecture for incenter and excenter loci of Poncelet 3-periodics

Let a pair of conics admit a family of Poncelet 3-periodics, and consider the locus traced by the incenter $X_1$ and by the excenters of the triangles in that family. Confocality conjecture. Only when the pair of conics is confocal will the locus of either the incenter $X_1$ or the excenters be a non-degenerate conic. The conjecture concerns the exceptional conic loci observed among Poncelet 3-periodic families; the supplied text presents it as suggested by experimentation and gives no resolution.