So I did a google search for "Moroso 84565" to find details on your catch can. First 2 results:

"The most beautiful vagina NWS - YellowBullet.com"
"Smart teen pisses off hungry frog?! - Dodge Challenger Forum"



I like the idea of having the oil catch can hooked up to drain to the oil pan like that. No need to check/drain the catch can.

It worries me a bit that there was no obvious problem/cause found that would explain your oily mess. With your catch can arrangement, you might just be masking the underlying problem that is causing excess oil to come through the breather hose.

It also doesn't make sense that any of the changes you described would have any effect on when boost kicks in, unless a boost leak somewhere along the PCV hose was unintentionally fixed while removing/re-installing parts.

It almost sounds like there was something wrong with the check valve or its installation that was allowing boost to flow into the crankcase through the PCV hose. That would explain both a lack of boost and excess oil blowing out of the breather. Did you find something wrong with the check valve? Was it not reliably closing/sealing, or was it installed backward?