Not how most of us natives pronounce it.
It is apparently how he pronounced it.
I am reminded of Chownings Tavern in Colonial Williamsburg. For years the people there pronounced it just as one would expect from the spelling.
On my last visit there (now 20+ years ago) the guide pronounce it "Choonings". So I inquired. The guide said that someone showed up several years earlier and claimed they were mispronouncing the name. When asked how he knew this, he replied, "Because I am one." This set off a year of research by the foundation before they decide the guy knew what he was talking about. So now it's "Choonings" as it apparently was 250 years ago.
ML/NJ