These three set screws (A2 below) are buried fairly far into the saw. To verify, unplug the saw, then remove the dust guard. It also helps to remove the throat plate, to allow light from above. Lower the blade assembly until you can see the riving knife clamping assembly in plain view while looking through the chassis of the saw. Shine a bright light and look as directly straight on as you can.
It may look like the saw is lacking the adjustment screws when you see the threaded part- but they are buried pretty deep. It's a black, 2.5 MM hex set screw. Please check the below picture to see what this looks like.
If they are indeed missing or were lost- DW745 Types 2, 3 and DW7480 Type 1 uses part # 330022-16 for a single hex set screw.