btw... the solution is.... one small now is tall... so exchange w with W in the 51 character string...
That's fucking stupid. It's unrelated to any of the information given. Why was the shit on the right of the image then? The OP made a typo in the given key and somehow that's supposed to be part of the ARG?
I dont even get it...
z69JZqlJn862D1ndx7oLVEMmVOlP1zewEeUCrsI7Roahzpeny7P switch(w,W)
-> z69JZqlJn862D1ndx7oLVEMmVOlP1zeWEeUCrsI7Roahzpeny7P
and then what? shift 6EQUJ5 times?
...
5KZnsvrXDcP7JFD7GCuZvifrbcBtK4kke8nHx6ibktgvPJxs4Lp
Where is the palindrome hint? I am confused and go to sleep maybe someone is nice and write a "for dummies" how to solve the last step so I can finish the pdf.