This is a common issue with 3d printing. Usually the solution is something along the lines of drilling holes into the model to let the resin leak out bearing in mind how toxic and damaging it is. Inserting an led inside the model to cure the resin (if its uv resin) or just chucking the model away. Iv done a lot of resin casting myself and with non uv resin if it has not been cured properly then unfortunately the model is essentially unfixable. On a positive side Warlord will likely replace your model as selling uncared resin is a big quality issue

It sounds very much like you’ve a resin model with uncured resin inside.
Whether it’s 3d printed or not, that’s almost always the root cause of weeping models. And if it’s uncured resin trapped inside, no amount of washing, priming, painting etc. will fix it, sorry.
That it’s weeping from points where you drilled it also suggests it’s something leaking out from inside the body of  the resin part(s).

But it’s also possible that if the only affected part is where you drilled and glued the barrel that your glue has reacted with the resin and caused it to break down? That your plastic pin melted suggests there’s some kind of chemical reaction going in here – either the leaking resin with the plastic, or possibly the glue with the resin, so I wouldn’t rule out your glue being the culprit here.

Uncured resin is solved by two steps: an acetone bath, and UV exposure. I had someone give me 3D printed models that were not cured, and these steps solved the problem in one day. Bath. Then put the model outside on a sunny day. Done!