I'm confused as you state you will "first install the actuator and see what happens". You said you had the actuator installed and it didn't fix it.
I still maintain, unless the mechanic states otherwise, that the throttle stop may not have been learned. They will run like this if the stop isn't learned, and this could all go back to when the air mass sensor was replaced. If he reset the adaptation and didn't relearn the throttle stop it will run like this.
Does the mechanic say there are now codes indicating a faulty EA control module, or does he just "think" it needs a new EA control module?