And God created Man -- who created QuickLoad.God didn't create quick load man did and as such it is not infallible. Had God created it He would have probably understood that 90% case fill in a longer case makes the 10% bair space just that much larger and that much further away from the primer flash.
To then not use that God-given brain is a waste.
That said, the 90% case fill reqm't (met by the OP BTW) has less to do flash distance as it does with ignition mass start-up once initiated. Again, the need for a Mag primer was stated clearly.
QuickLoad is a superb resource -- and very dependable in finding safe mid loads with which a chronograph can then fine tune both velocities & pressures as the shooter progresses.
The OP's load was safe by a 50% margin in pressure.
QuickLoad did, however, note it was on the margin for case fill.