I cannot speak for ABC Disco, but I do know that African Alphabet was partially dubbed... as soon as Kermit and the African AM's start singing the letters of the Alphabet the first time, it's the letters of the Hebrew Alphabet, but when Kermit sings about what each letter stands for (second verse) it's in English.
I cannot remember ABC Disco, but if they sing the Alphabet twice, chances are the first or second time will be Hebrew, and the other time will be English. But it's just a guess...