If he can post some sample of what he is doing we can probably fill in the blanks.
Generally you would want to run your two turrets into position, with the chase/deeper tool set at the respective distance and P-Code those lines as they match up. Then if they meet (hold) at the start point and will be travelling the same distance at the same rate, you will follow through properly. The P Codes can be done in tandem (same code on both sides) as a hold point to match up or you can just alternate as you let one or the other turrets move. Some times you get errors if you don't properly align your spindle codes. Spindle speed changes often need to be done on wait coded lines for each of the turrets.