well the first thing I I will tell him to do is change all spark plugs .. and switch the coil form another cylinder.. and clear the fault again.. and drive it a bit..
and by I prefer to delete the cat converter because it its expensive.. and the emission regulation in my country are not that strict.. so its not worth replacing unless the suv needs it to function properly.
another question.. if o2 sensor is bad.. wouldn't it show up on the scanner?