With the ejector designed to deform the primer you'd think one should be extra careful when manually ejecting a round that didn't go off.
Never actually heard of an accident that could have been caused by that, manual extraction is of course infinitely less violent, but still...

About "the cam loaded barrel nut locking plunger v the mag cover", I've only found a conversation about how to disassemble those plungers, not a detailed description (or images) of those plungers themselves unfortunately.
There is an enormous amount of wonderful information strewn across all those discussions, finding something specific is not so easy.