Model not getting me results I want.. correct thought to use?

At work, I have delegated a portion my work to an individual outside my team. I’m waiting for him (lets call him Alex) to complete the work with high quality and on time so I can move it to the next phase. But Alex is not giving this the attention it needs, and is not as familiar with the content as I am, and I’m afraid the work will slip. I know that these are thoughts, and I’m trying to flip them around to make it work. I ran a couple of models that can give me the outcome I want, but I still see myself doing most of the work regardless of the thought. The difference is that without the model, I’d be angry while doing the work (since Alex should be doing it) but with the model, I’m more neutral (at best). But this is still not what I really want as the result.

Is there a different approach?

C: Alex has not started the work (I know this since I asked him)
T: He should be proactive and do the work, give it the attention it needs and keep me updated. I should not be doing this.
F: Anger
A: Do it myself, complain to myself and my boss (see if I can plan better next time to reduce my dependency on Alex)
R: Send out the work to the next phase

Intentional model (but it does not give me the result I want)
C: Alex has not started the work
T: He does not know the work as much as I do. He needs more help and I can step in and do it quicker than him
F: Neutral, some compassion
A: Do it myself (or let him do what he can and then clean it up / finish it)
R: Send out the work to the next phases

Model with ideal result
C: Alex has not started the work
T: I will ask politely but firmly, and give him a deadline
F: Neutral, Confident
A: Alex completes the work as planned (but I know this is not likely to happen)
R: Send out the work to the next phase

No matter what model I use, I don’t get the ideal result that I want (which is for me to be able to truly delegate and step out of the way). I feel its naive to expect a different outcome from what I think will happen with a 99% probability (him not completing the work on time), so changing my thought to “Alex will do a great job” will likely not cut it. Thoughts?