How do u get the key or object u need to enter?

and wut does the corpes' hand do for ya?

clueless about those two things

spoiler
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The corpses hand is Grimgnaw's quest item

Port Llast mines: Find the four escaped convicts and return their ears - then the mayor will give you the key to go and find the fifth (and last) convict.

Is the Quest Alignment dependent? cuz im Lawful Good

the only Mayor I know of is the one in Charwood Village. is there another Mayor? cuz i already finished that Quest with Quint and Karlat Jarheg.

I think the mayor he's talking about is the one in the mercenaries barracs in Port Last.