2003 Chevy Suburban Coolant Leak

Had a cooling system pressure test done and was told I need a new timing cover gasket. Was told this is a result of using dexcool antifreeze. Was told the antifreeze eats away the gasket and if not replaced will cause other engine damage down the road.

Is there a way to fix this without replacing the gasket? Didn't know if there was an additive that would seal the leak or if the gasket really needs to be replaced.

Thanks