A jumble of classifications of Celtic

[Arjos]

That's one of the many hypothesis, another is uolko- for wanderer.

Volk, seems blatant to me that it's a later term, since as I said, it started as a description of their neighbouring "foreigners", ie culturally different people, (Keltoi, more specifically the danubian Uolkai). And it was extended to any foreigner, thus the meaning "people".

The point here is that the the distinction between germanic and celtic, took form at a much later period. So it doesn't make sense to introduce a pre-germanic root for those names. And again the one you mentioned, is hardly fitting for a personal tribe/group, as it means something "external".