Sad and a pain in the wallet to have this happen. I think many of us have been there. Good job stopping, cutting open the filter and regrouping.
Once this happens, everything will need to be taken apart, cleaned inspected and passed/rebuilt or replaced, even the heads. I had an engine built several decades ago that had dirt and debris in the oil passages that were supposed to have been scrubbed, but had not been. The guy who built it nicked the crank with the rods when he threw it together, and it gouged the rod bearings as well.
I was just a kid at the time, and ended up suing the guy in small claims court and won. It was a shallow victory. Best of luck.