Your fore arm a is Curtis release and even though the drawings state ejector which is right, because it is ejecting the shell to be removed from the extractor, not ejecting the shell from the gun.
If you look closely at the print the trip stem 64 RE has a groove at the end and this is where the spring lock 41 RE fits into. When you push the stem in it releases the spring lock from the barrels loop which has a slot on each side, releasing it from the barrels to be removed.
Removing the button will not help in removing anything and quite possible you could break the spring lock.
If you look at the picture I posted your screw is missing and will not let the it function properly to slide. I am not sure what size that screw is but either 8-32 or 10-32 and only long enough to catch the slide.