On boosted motors the PCV system needs a check valve on the vacuum side, that will close once boost/positive pressure is seen. Then the other side which should be a vented/filtered catch can will allow any positive pressure that gets past the rings to vent out without causing positive crankcase pressure. I'm not sure if the mightmouse has a check valve but if you don't have the check valve put one in. I do this on my boosted LS builds and never have an issue. I get the check valve from McMaster Carr.
Pass side valve cover vent to catch can with filter (this is your fresh air inlet into the engine if the PCV system is working). The driver valve cover has a PCV valve in the valve cover and lets just say its hooked up to the intake for vacuum. You put a check valve between the intake and the PCV valve which is open when the intake sucks from the valve cover, but closes if you apply pressure on the intake side. THis is so boost can't go back into the valve cover/crank case and blow out seals. The pass side breather now switches from a fresh air inlet to a pressure outlet and the catch can catches all the oil that tries to come out with it and collects it for you to drain.
I bet if you fixed the PCV system your leak will probably stop and its worth a try before freaking out over the cover seal. I haven't done that much work on a Hemi before so not aware of how things go together but front seals are usually cheap and easy to replace if you have it all out for a cam swap. I would replace at that time with a quality seal just to be safe.
