I don't know if right or wrong but driving the oil pump with the same serpentine as the blower raises question in my mind.
Blower drive is high power, say 50 horsepower or more. Oil pump has much less power requirement. Will the oil pump drive compromise the blower drive? High power drives are sensitive to geometry, slack versus tight side, pulley wrap, backside idlers, etc. are considerations. If you throw the blower belt you lose oil pressure. Again, not saying good or bad, just asking the question.
