In my experience for codeshares the IB purchase predictions are off, in the above case, the base fare is probably 2649/5 (it uses 5 instead of platino 8), so 530, then it only gave the DOH-HKG cabin bonus of 350, so that's the 880 it quoted. There should also be FRA-DOH 175, because that distance is 2853mi and very inefficiency just outside the 3000mi needed. Also the base fare might be 530 but I'm sure there's some carrier surcharges aka YQ that you would also get some avios/EP for.

That's quite a long stopover, and, if you start in MAD you get better EP as then the distance is > 3000mi. If you buy the thing through QR instead of IB you'd get an easy go calculate 1250+1250.

I hope you find this fun as it makes this "hobby" instead of a chore...