Before you take a course that you believe with your current pistol skills will fail, you may want to find an instructor that can teach you the the basic skills necessary to competently place shots in the zone. I get to see many security training and NYC police officers and NYS Troopers training for their qualifications test.
If you practice and dry fire the timing part won"t matter as they give you ample time to shoot each stage. Practicing smooth draw and trigger control is much more important in any aspect of the qualification. Research, most ranges have a person on hand to help with your training for a relatively inexpensive fee.
...Ron