Trying to ORC credit to SAS EB will turn out fruitless because EB will keep denying any request for EB points because you didn't travel with a Star Alliance partner. The issue for EB is that if EB grants points for non-existing UA flights EB has nowhere to send the bill for the EB points you have received. Normally, UA will have to pay EB for points that EB grants its member for a UA flight, but if there is no UA flight or pax was not on the UA flight that EB has granted points for, UA will deny any request for remuneration from SAS EB.

The key to have this solved is not EB, it UA. You need to persuade UA to let EB grant EB points for the missed UA flights. I'm not sure if UA is prepared to do that; sounds close to impossible to me.

ORC is only straight forward if you apply for credit with the same airline/FFP that caused the disruption, i.e. you apply to SAS EB for points for a SAS flight, or you apply to UA MP for miles for a UA flight.

You will most likely get nowhere with this. If you are a member of BA or other OneWorld partner, ask that FFP for miles/points for the Alaska Airlines flight.