There should be a comma before "while". You are right that "while" should not be at the end of a clause. In this case, "while" starts the next clause.

It appears you are not familiar of the different usages of "while". It has two major usages: 1) during some time frame - "While he was studying, I read a book". 2) with a certain condition or state - "While he's good at math, he falls short in history". #1 is strictly time related, similar to "when" except that it signifies longer period. #2 concerns not time but a state or condition, and has the same meaning as "whereas". In both cases, "while" can come in the beginning or middle of a sentence" since the sentence always has two clauses and while comes at the beginning of either one. For example, "I read a book while he studied" (1), or "He's not a good actor while good looking" (2). The example you cited has "while" in the middle of the sentence, not end. You can consider the sentence with the minor clause ", on the other hand," taken out, which will show the structure more clearly.