I cannot create a list on either the Page or SubSite for several Excel files. I am getting the same warning message telling me the same thing shown below (Column " does not exist. It may have been deleted by another user.) then the URL.
I had the same issue. I decided, based on the responses here, to copy the column headers out to NotePad. Sure enough, many of them had quotation marks around them, but it didn't display in Excel ¯_ (ツ)_/¯. Might be because I consolidated several lists into one. In Notepad, I deleted the marks, then pasted the name back into Excel or in some cases, deleted the column header name and retyped it.
I ran into the same problem and found that there were several CR (carriage returns) within some of column heading cells (as opposed to wrap text). After removing all of them, I was able to import/create a list from excel. (The CR mentioned is entered within the cell by holding "ALT" then "Enter". It doesn't appear to leave a character that I could find when copied to text.)