Are the stresses actually compressive, or are the tensile stresses lower?
If the stresses are actually compressive, then the prohibition stands. The allowable stresses listed in Table 5/5A are allowable tensile stresses. In compressive stresses, the failure mode is buckling. Above the temperature listed in Table 4.4.1, the failure mode becomes creep buckling - which is something that the allowable tensile and compressive stresses do not consider.
You cannot make the determination of whether creep buckling governs unless you actually perform a creep buckling analysis - the calculations provided in Part 4.4 do not consider that failure mode. Therefore, you are unable to make the statement "These conditions never govern...".