Azizi, I never heard it any other way than 'Jerdon' (Jurdon) in Georgia, Alabama and Texas. Until well after WW2 and the movement of northerners into the southern cities, both whites and blacks used that pronunciation. The family name Jordan also was pronounced 'Jerdan' or 'Jurdon." My wife has some relatives with that name. They said that they were Jerdons, that Jordans were Yankees.

"Roll, Jordan, Roll" was collected in Auburn, Alabama in 1915 as "Roll, Jurding, Roll," another southern variant, from a Negro revival meeting (White, N. I., "American Negro Folk-Songs," p. 87-88), Folklore Assoc. Inc.

Verse 1:
Roll, Jurding, Roll, roll, Jurding roll;
You oughter been settin' in the Kingdom
To hear sweet Jurding roll.

William Arms Fisher, in his notes to the spiritual, "I'm Just A-Goin' Over Jordan," says that "Jordan is usually pronounced Jerdon." 1926, "Seventy Negro Spirituals" (for low voice), pp. 88-89, Oliver Ditson Co.   

I have never heard the last syllable as 'done.' (Day is done; rhymes with Sun).