You did not state why you believe this name to be Polish. It is important to go by the sound of the name during this time rather than the spelling...people were obviously hearing something different than Wernicke if they were using all these weird spellings for this one particular family.
The other poster may not have been correct if, in fact, the name is Polish, because in German the icke part of the name would be pronounce ick or ick-a in our English language, making the GERMAN named Wernicke be pronounced vur-nick-uh. If you've got the insky sound at the end the you've definitely got some Eastern European in there. With Eastern European the W would still be pronounced V and any sky sound is typically spelled ski with the sound of skee. The spellings you are showing don't account for an r sound in the middle of the name as it does with the Wernicke spelling. Euro name endings are typically spelled ski instead of sky (which is a westernized spelling). The only question seems to be whether there is an n sound in the middle or of the name or not -- which you are showing sometimes being there. So the name is either Weniski or Weninski, with my money on the first one.
Go to familysearch.org and put in Weniski with no place of origin and see what places pop up.
https://familysearch.org/search/record/results?count=20&...~