If it was mine, I would just chamfer the hole and put an o ring on the bolt. Kind of like the transmission cooler line fittings
The pump bolt that appears to be leaking has the factory rubber washer on it already, and I put RTV under the head of all the case bolts, including the one that looks like it's leaking. I also put thread sealer on all of the pump and case bolts. That's why I'm at a loss. The area under the converter snout looks like it's dry, so I don't think it's the converter seal or the pump o-ring. I've checked the converter itself both times I've had the trans out and there's no fluid on it anywhere, so I don't think it's coming from the converter itself. Makes no sense to me at all.