Environment-dependent mass splitting to suppress solar capture in the inelastic-doublet interpretation of the LZ event

The inelastic electroweak-doublet interpretation of the $248\mathrm{k}\mathrm{e}\mathrm{V}$ recoil energy event reported by LUX-ZEPLIN faces strong constraints from solar capture. We propose an environment-dependent mass splitting generated by an ultralight scalar coupled quadratically to electrons. Its density-induced expectation value enhances the splitting in the Sun while preserving the laboratory value, providing a mechanism to suppress solar capture. We derive conditions for this mechanism and examine constraints from stellar cooling and electron-mass variations. We find that this scenario is phenomenologically viable, while it suffers from severe fine-tuning of the scalar potential.