Magnum R/T heads - do they Have wet corner exhaust manifold/header Bolt holes???
I don't think they are supposed to have wet holes. But I say that with the caveat that my R/T heads had one set that did not and another that (best guess) had enough core shift that the machining just barely broke threw. Could be that the machining on the one was too deep, too, as I have valve cover bolt holes that I didn't use that leaked oil for the same reason.
So, my guess is the intended design does not have wet holes.
I would suggest loosening the bolts some and seeing if you get leaks and go from there.
I might add that if you didn't seal them before and didn't get leaks, they are probably fine. I thought mine were dry and had a coolant leak after I got it running and had to add sealant to the bolts. Don't remember what I used though, sorry.