Established romanization conventions for various Amami dialects 
 is posting a false accusation around Wikipedia: I made up my own romanization scheme. I have no idea why he is so confident. He must realize the existence of unknown unknowns, in order to stop damaging Wikipedia. Maybe I need to recall Hanlon's razor, but being extraordinarily stupid is almost malicious.

Of course, it is an established linguistic convention to use ï (and ë) for vowels of various Amami dialects that cannot be found in Standard Japanese. And they correspond to kana ウィ and ウェ respectively. An example available online is . If you need an English source, check Moriyo Shimabukuro's The Accentual History of the Japanese and Ryukyuan Languages (2007), for example.

Ryulong added weird spelling kamwiyaki to the article. The Web is now tainted by Ryulong's use of the spelling, but at the time of his edit, there seem to have only two sites used the weird spelling. Both sites are based on Okinawan information. Obviously, they are unaware of vowels Okinawan dialects does not have.