A source (reliable or not) is always important when somebody comments a supposed origin/meaning/etc. of a name. So the name of the particular philologist is important. Perhaps somebody can say if this philologist has in general a very solid knowledge, and his/her affirmation can be considered (Joan Coromines, e.g.), if he/she is simply a dilettante, if he/she is usually solid in some languages, but his/her knowledge about other languages is very inexact...
Moreover, some apparently reliable sources (philologists, onomastics authors) make a big number of mistakes. So to know that a "considered as reliable" philologist/author made a mistake is important to estimate his/her reliability (a little mistake + another little mistake + another little mistake +... = a very big mistake = a not as reliable source).
So, since in this case the source of your affirmation is this philologist, I'm very interested to know his/her name.
Lumia
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