If they do the job properly, there is ZERO need for them to acknowledge receipt of an email. ZERO. They do the job and everyone moves on to the next thing at hand.
Inherently, you distrust them. You may say you don't distrust them, but you do. Your language and fixation on their "acknowledging receipt of the email" says there is a level of distrust.
I will try to stay out of this from now on, because as others have said, you refuse to see this from any other viewpoint other than your own.
🤦♂️I can't believe you still are misunderstanding me. I have no doubt they will do the job properly, but I need to have confirmation that they know what the job is. I can't expect them to act on information that they did not receive, obviously. If they do not reply, then I have no idea if they read the email or it got lost in their inbox, accidentally deleted, etc. So this absolutely has nothing to do with trust. You are simply, 200% w-r-o-n-g on that.