Massive oil leaks.

I thought I had a massive oil leak once on an engine and it turned out to be my fault. Left the oil cap off...at full power it slung oil out. What I learned from that is 1-2 quarts can cover a lot quickly and look massive. I put the cap back on, cleaned up the mess, and pressed on. It was a different engine type, but what I'm getting at is it might be something simple. Check your oil filler cap gasket...was it missing? Like the idea of adding oil and seeing where it's leaking from. Appears to me you don't have the suck from one breather via pull from PVC on the other which is important to keep pressure from building. Hopefully blew an easy to replace gasket like both valve covers. Sorry you had this happen. Good luck.