Paper 20 in the Non-Holomorphic Fractal Series. Papers 18 and 19 built a calibrated Borel-plane atlas for the non-holomorphic Bird map and found that natural Class C observables (orbit-multiplier, WBA, and alien-strength Watson ladder) are Feigenbaum-blind at current resolution under a gamma-family Padé–Borel skeleton with strict G1–G4 artefact filters. Here we extend that atlas by introducing explicit alien-corrected inputs derived from the Watson-side alien calculus of Papers 13–17 and feeding them back into the same Padé–Borel machinery. Our computations show that the calibrated gamma-family probes detect a planted Feigenbaum-like pole with excellent stability even after first-order alien corrections, but the true Class C observables remain empirically Feigenbaum-blind on the positive axis up to N ≤ 80 and over a moderate Borel scale band. The negative Class C verdict is thus significantly strengthened.