Your status as oneworld ruby is irrelevant in this case which as Scottishpoet points out does not get you seat selection. QR metal in I class though allows for seat selection lounge access in all locations. This would be true even if you purchased through QR itself where I equals a Convenience fare which comes with those benefits.
What might require an extra step is if the seat map does not display for you to enable seat selection. In which case you may have to call QR or use their chat function to get seats assigned.