Yeah I don't get on with Epiphones at all. Tried a couple and a lot of harmonics are basically "missing" lol. Not a great choice if you want to learn pinchies.
Sorry to burst your bubble, but that cant be true for a particular brand - no matter what brand of guitar you speak of.
A string will have all the harmonics it should as long as the string isnt knackered or that there is nothing stopping the string from ringing out.
I have worked on a lot of the Gothic vs and they are some of the better guitars that Epiphone ever made
The Epiphone goth V will be pretty damn good
It doesnt try to be all things - so there is no cheap floyd copy that just wont perform
Buy it , put fresh strings on it and get playing
If anything allow some extra cash to have her set up or at most fret dressed at some point
Alternatively Jibidy's Peavey will work well if its not too glam for him.