Not all systems have a pin. Many microlight systems use a "one-shot" twist system that breaks some cable ties. A few older systems just have a single pull-handle.
Plus, post-crash, I'd not trust the pin to keep it safe anyhow given likely internal distortions to the system and operating cable.
I am not a rescue expert, but I wrote the original safety regs or ballistic chutes in the UK, and have signed a number of systems off as a CAA design signatory, which probably makes me an expert in something.
The best you can do, in my opinion, is identify the drogue / rocket exit route, and keep everybody well out of the way of it during the rescue and subsequently cut it out of the aircraft working carefully to the sides of the rocket and find an explosives expert to take it away for you and do whatever explosives experts do to things like that.
G