5KZnsvrXDcP7JFD7GCuZvifrbcBtK4kAe8nHx6ibktgvPJxs4Lp should be a valid private key. It doesn't include a zero, capital o, capital I or lowercase l.
it is the key for 1nchRAYGJofxyrkuhbL1CGYtD5x8Lowi5 according to blockchain
The checksum doesn't verify though.
blockchain seems to think it does
https://blockchain.info/address/1nchRAYGJofxyrkuhbL1CGYtD5x8Lowi5The public address generated from the 32 bytes within the base 58 string we found (after the 0x80 byte) will obviously be valid. But the point is, the private key we find (in base 58 format) is not valid since the checksum bytes aren't correct. So the transformation is a bit off I think.
Again, I think there is either more to the shifting key or the algorithm is a bit off.