I do injection molds (different type) on my Taig 2019, and I think you will find its easier and faster to just cut your mold, and center spot for holes for alignment pins to press in afterwards.
I have been making fishing bait molds, and I just cut the whole thing (multi cavity usually) and spot for clamping screws, and pins with the mill. Then I use my floor drill press to do all the drilling with various size bits as needed. Then I have a second smaller table top drill press I use to tap any necessary holes with a tapping head. This seems to be the fastest for me, and the alignment pins are ALWAYS aligned properly in relation to the cavity, sprues, vents, etc this way. I don't have to go ape trying to position the pieces of stock perfectly on the mill and zeroing the piece relative to the mill this way.
From what I see in your picture you are going to be using some very small cutters. You may want to consider the following to make it more efficient.
1. Make an enclosure for your mill.
2. Set up a flood coolant recirculation system (with filter screens).
3. Make a clamp for your mill to hold a high speed spindle like one of the 2.2Kw ones from Keling or even a mid size wood router. (I am currently using 1HP Bosch Colts, but am considering trying the 2HP Porter Cable. Also considering the VFD spindle from Keling.)
Higher speed spindle and flood coolant will make a huge difference in your cutting speed and cutter life.
Also, set yourself a maintenance, lubrication. and adjustment interval. If I am happy with .01-.005" I can get by with 30-40 hours of run time, but if I need to keep it under 0.005" then I need to do it every 8-10 hours of run time.
(I have run jobs in excess of a million lines of code, and jobs of several hundred thousand are common.)