Intake gasket opinions

you probably don’t sit much at idle (or your highest vacuum reading) during the dyno? If you’re leaking oil at the intake manifold, it’s only going to leak significantly at idle or cruise, then the gasket must become over saturated, then can leak oil through to the ports. On the dyno, I’m sure you’re loading the engine up hard and have minimal manifold vacuum except during warm up. Maybe this explains why it didn’t show up until in the vehicle.