You cannot read oil temperature from the climatronic "secret menu". Some lists report that its possible but so far as I can see its a myth. From this menu, you can only read things that the climate control might care about or may help in diagnosing the HVAC system. Oil temperature, boost pressure etc don't fall into that category.
To check for sure, use VCDS and look at measuring block 134, field 1 - this is oil temperature. Was monitoring it myself just the other day.