Does the dome thermometer indicate a different temperature than the thermometer at the grill/grate?
This is not surprising. The grate/the grill is closer to the fire. It may happen that the temperature measured at the grate is much higher. A difference of, say, 35 degrees is certainly not unusual.
Using a plate setter can also affect the temperature at the grate and in the dome. That can cause temperature differences in different places in your kamado.
Tip: want to achieve a high temperature for e.g. baking pizza? Then keep in mind that when your dome thermometer shows the desired temperature, the pizza stone has already reached a much higher temperature.
So what is the ideal temperature for baking a pizza? There is no single answer for that.