Secondary-Mass Context in the Planck and Gravitational Couplings from the Compact Fiber develops a secondary-mass context rule within the compact-fiber/Larson/Nehru mass architecture. The central result is that Planck/action conversion and gravitational mass-unit conversion require different secondary-mass corrections because they correct different structural operations. The Planck/action calculation uses the full particle secondary mass, s_h = m + e, while the gravitational calculation uses only the gravitationally intrinsic secondary mass, s_G = m. The accompanying reproducibility materials evaluate the Planck/action constant, the gravitational constant, the dimensionless proton gravitational coupling, and the four assignment-control cases. The structurally predicted assignment gives residuals of approximately -7.8 ppm for h, +160.2 ppm for G, and -32.8 ppm for alpha_G^(p). The result is presented as a bounded constants-sector test of the secondary-mass context rule, not as an anchor-free derivation of the gravitational hierarchy or a modern SI realization of dimensional constants. The calculation uses the stated Larson-era anchor system and imports the compact-fiber carrier structure from prior compact-fiber work.