Was the Qur'an revealed in 10 different ways of recitation by Angel Jibreel? To my understanding, there were only 7 different unique ways in which it was revealed by Jibreel to Prophet Muhammad sallallahu alayhi wasallam, and these 7 would encompass all of the uniqueness of how it was recited too. This would mean that in recitation the maximum number of unique variations would be 7 as divinely revealed by Jibreel.

How then do we arrive at ten unique ways to recite and say they are all authentic? Could one draw the similitude of accents within a particular dialect? Like in the USA one from New York speaks differently than one from Texas although they use the same dialect? If this is the case, how were all 10 accents approved of divinely? Please shed some light on this.

The 10 recitations exist because the differences in the Qur'an are not limited to dialectic differences but include grammatical differences and alternative meanings to verses.

Depending which opinion you follow regarding the preservation of the Ahruf, there is a different understanding of this. Based on my view that the seven Ahruf are preserved in the ten recitations, the ten recitations can be regarded as an amalgamation of the seven Ahruf, or as Dr. Yasir Qadhi states:

“The differences in the qira'aat are remnants of the differences in the way that the Prophet taught the recitation of the Qur'aan to the different Companions, and these differences were among the seven Ahruf of the Qur'aan which Allah revealed to the Prophet. Thus, the ten authentic qira’aat preserve the final recitation that the Prophet recited to Jibreel. In other words, the qira'aat are manifestations of the remaining Ahruf of the Qur’aan.”[1]

Allah knows best.

Reference: 

[1] Dr. Yasir Qadhi, An Introduction to the sciences of the Qur’an, p. 202