Sometimes stats can overlook nuances. Even so, ignoring stats in many cases means you depend on inaccurate prejudices or incorrect assumptions.
Weathers managed to blow a save without giving up a run, but he's only blown 2 all year. His lifetime stats and age aside, lately he has been an extremely reliable reliever who has done what he's supposed to do as a reliever, and doing it better than almost any other pitcher in the bullpen.
Weather's isn't a long-term solution for the Reds and I'm sure he knows it. But if he were to continue to pitch this well for the rest of the year, he will be an incredible asset to the team. The OP said Weathers doesn't belong in baseball. His accomplishments as of late show that he does.