I wouldn't worry too much about the difference between a clicker that is connected to the bow and one that is not, so far as the non-anticipatory psychotrigger aspect is concerned. You can force the type of trigger that is connected to the bowstring by a string to click consciously if you want to. Same as you can force a rifle to go off when you want it to, even though you are supposed to be squeezing the trigger until the release is a surprise. For any trigger that is supposed to be non-anticipatory, you have to play the game the way it is supposed to be played.
The thing you would lose by using a trigger that is not actuated by the bow is that you wouldn't get a draw check. However, if you want to use a dead release, you have to find a trigger that will work without being actuated by a movement of the arrow.
Like David Mitchell, Jim Casto's program has helped me more than anything else I’ve tried. I still have to go back to Jim's drills occasionally to regain the feeling of total control of the bow. Joel Turner also has a lot of good advice about total control of the bow in his course, even though I believe he is wrong, at least in my case, that a subconscious release necessarily leads to target panic. Maybe in other people's cases, it does lead to target panic. I think there may be different things that trigger target panic in different people.