@lemouth, I believe the production of anti-proton and other anti-particles has validated CPT symmetry.

Not is has not. The validation of the CPT symmetry include many extra tests that are still on-going.

Now my question is this: The first statement affirmed that annihilation occurs when antimatter is couple with matter. The second statement on the other hand, is talking about the annihilation of proton and neutron in the neutron skinned nucleus. Is that not contrasting? Because my interpretation of the second statement is that the proton (matter) and neutron (another matter) will annihilate. Whereas it should be anti matter versus matter.

Let's take a particle A and the associated antiparticle Abar. WHen A meets Abar, they annihilate. Here, the story is different. When the antiproton approaches the exotic nuclei, the first thing it will do is to modify the nuclear dynamics. Moreover, the nucleus is surrounded by neutrons and not protons (instead of having A and Abar, we are having A and Bbar that does not annihilate). There are several models on the market that describe how the nuclear dynamics change, and this new dynamics will induce proton-neutron annihilation. In order to know better the correct modeling of all of this, we will soon have PUMA :)

Is it clearer?