Kuy(r)kendall: a Hine follow-up

As I was finally closing the door on all the Hine photos AND all the interviews about them, one name caught my eye: that of Ralph Kuyrkendall. It struck me, of course, because it looks Dutch, but it also looked, well, wrong. Was it supposed to be Kuykendal? Kurkendal? Kerkendal? "Kuirk" is not really an appropriate letter string. But then, Hines often misspells names (e.g. "Albernesi" for Albanese.) But no, Kuyrkendal seems to be how it is spelled. His granddaughter reminisces: 

He said that there were a lot of people in Mississippi with the Kuyrkendall name, but many without the “r.” He would say, “The people without the ‘r,’ were the ones that were caught stealing chickens, so they had to drop the ‘r’ from their name.

A "lot" of Kuyrkendalls in Mississippi! Indeed, a little googling reveals a number of Kuyrkendalls all over America today: Texas, Florida, Louisiana. Is the r part of the name or not? One blog, commenting on the name of a "Kuykendall" playing college baseball, says it's pronounced with an R even when you don't see one! Ever more mysterious. 

After sifting through a certain amount of fora of people musing about the meaning of their name, I found a book giving the genealogy of the name and tracing it back to one Luur van Kuykendal who immigrated in the 17th century. Forced to adopt a proper surname by the English, he attached the name of his home (summarized here). Luur was elsewhere described as from Wageningen; there is a village called Cuijk not far from there, in the so called Land van Cuijk.  There's no "Kuikendal," so one has to imagine that the area was so described centuries ago. Then I suppose the many descendants of Mr. Kuykendal moved south, and many of them ended up in Mississippi. (Similarly, many of the Tanguays and Castonguays of Quebec today are related to one very prolific seventeenth-century fellow of that name...)

That's all very well, but it doesn't explain my initial question, which was--why the R? If the original name was indeed Kuykendal--and not the R variant as Ralph imagined--how did the change creep in? 

Then it occurred to me--the r version seems to be most common in the South. The South, historically, spoke (and speaks) a non-rhotic dialect; something written  "Kirk" would sound like "Kuhhhk." Meanwhile, out in Cuijk, they speak a dialect with a lengthened sort of diphthong for "ui." So quite possibly some southern Kuykendal, tired of being called "Coy Candle," put an r in, to convey the shared diphthong found in both the English and Dutch dialects in question. Ironically, as American English moved to being rhotic, the r became pronounced, and *that* pronunciation became canonical--so that a pronunciation with an R is prescribed even where none is written!
Linguistics is crazy.