To tackle the critical challenges of difficult stress relief, unclear energy release laws, and high outburst prevention difficulty in deep cross-measure coal uncovering, this study identifies that the energy accumulation and chain failure of structural inclusions under high stress-gas pressure gradients are the core inducing factors for coal and gas outburst. A novel synergistic outburst prevention technology of blasting-injection weakening combined with grouting reinforcement is proposed. Specifically, one blasting-injection hole and twelve control holes are arranged ahead of the heading face. Through a sequential implementation of pressure-relief blasting for prefabricating fractures, water injection for fracture expansion and pressure reduction, gas extraction, and grouting reinforcement, a "strong-weak-strong" structural zonal layer is formed. A numerical model was established via FLAC3D to simulate the proposed technology. The simulation results show that with this method, a stress relief zone of approximately 10 m is formed on both sides of the roadway within the coal seam, with the average stress reduced to 2.5 MPa, indicating a significant mitigation of stress concentration. During the coal uncovering process, the elastic energy release in the control zone is reduced by two orders of magnitude compared with coal seams treated by conventional methods; the maximum displacement of the roadway roof and floor is decreased by 60%, and the scope of the plastic failure zone is narrowed, which verifies the remarkable outburst prevention effect of the technology.Furthermore, parameter optimization confirms that "Strength Grade 4" is the optimal grouting parameter. It achieves the optimal balance among pressure relief, deformation control and energy regulation, and avoids the attenuation of marginal benefits caused by excessive reinforcement.