It doesn't mention the speed at which they roll differently.
What is remarkable is that the much larger Tempest and Spits outroll the 109 at every or higher speeds although they have to move much more area and mass.
So the 109 has to be quite worse from an engineering pov concerning roll rate.
No, you misquote. It states that there "is practically nothing to choose" between the Tempest V and the Me.109 in rate of roll below 350 IAS. Also, "The climb of the Me.109 is superior to that of the Tempest at all heights".
Eng