Research substantiates that both “lion” and “hunter” are plausible according to analyses of Proto-Highland Eastern Cushitic wherein “kas” is to stab, pierce or cut and the suffix of “wara” creates “agent nouns”. In modern “Ethiopic” languages such as Tigrinya and Ge’ez (as well as in some other African languages) the word “Wagatwara” means “hunter” and in earlier etymons of this word the “g” is rendered a “q” and the “t” is rendered an “s”.
But just now, looking through a Hobyot vocabulary (Nakano 2013:215), I came across an entry that makes all this discussion unnecessary. In Hobyot, "panther" is ḳáyṣ̂ər, with a plural ḳaṣ̂áwrət - clearly related to the term used in the Qur'ān, and clearly (given the ṣ̂) not borrowed from Arabic. The meaning corresponds closely enough to most commentators' consensus on qaṣwarah, while the location - in the extreme south of Arabia - helps explain why the term might have been associated in their minds with Ethiopia. In fact, the irregular correspondence of Hobyot ṣ̂ to Arabic s would suggest a loan into Arabic, rather than common inheritance, even if we didn't know how much this word puzzled the commentators.
Incidentally, the minority interpretation "archers" is presumably based on Persian, where -var added to a noun means "possessor of" - presumably, Arabic qaus "bow" + Persian -var would yield "bowman", and the feminine suffix -ah would form the plural as so often with nouns of profession. In light of the Hobyot form, it also should be clear that the majority of commentators were right to reject this interpretation.