So I tried to book TOS-LAX (TOS-OSL-ZRH-LAX) on KrisFlyer and I was told that's not allowed. I pressed for a reason but I was told it exceeded maximum level. I got it ticketed on United for 70k miles just fine.
I had to change it to OSL-ZRH-LAX instead and pay for TOS-OSL out of pocket.
Anybody knows why this is?