And the intent was to have Data be the handiwork of ancient aliens, Klingons to be UFP members, and Leslie Crusher to be a pretty little girl. The intent was dropped at various relative points: Leslie became Wesley for the very first episode, Data became Soong's son by middle first season, having remained indeterminate until then, and Klingons actually were canonically referred to as members once before the intent was nullified.
The intent to have Captain Rixx be Bolian just represents another point on that continuous scale: he was never established as one, and all the evidence conspires against him being one, as he doesn't look the like one!
Perhaps Rixx would be half Bolian or something, losing his blueness and transverse color patterns on the skull that way - and Mitena Haro would gain her hair and eyebrows the same way?
TNG featured a Federation emissary who was a Klingon...