I would argue that a Flaw that doesn't actually modify one's behavior isn't actually a flaw. Thus, if you have 2 interpretations - one of which does nothing, and another that does something - then it's probably the one that does something that's the right one.
EDIT - and in reading up on the flaw itself (RoP:F, pg. 52), we've got "...The fairie must attempt to flee the ward, and its body is destroyed instantly by the ward's touch." - Obviously written with faries in mind. However, if we took this literally, then some of the other virtues (such as Farie Speech, pg. 50) wouldn't work either, as it specifically references the fact that it works for faries.
So, we're left with 2 possibilities: that some virtues and flaws don't work for Fairie-touched characters (despite being in the list), or that they do. My interpretation would be "if it's a farie-touched mortal character, then replace "farie" with "fairie-touched". Alternately, if you don't want to do that, remove any of the virtues and flaws that reference faries (as opposed to "characters", which is what most of them seem to use instead) from the list. However, that seems unduly harsh.
That being said, you may be running up against the 5th edition issue of "everything is either -3 points or -1 point." In previous editions, you could have flaws that were greater than that; ie, a single flaw worth (say) -7 points. While I can understand the desire of the authors to use the Merit/Flaw system to create well-rounded, interesting characters (as opposed to crippled one-trick ponies), the end result is that sometimes we get virtues and flaws that seem over- or under- valued.
Diedne Magic, in the core rulebook, is an example of this; it's a major virtue, but it comes with its own major story flaw. Unfortunately, as "greater than 3 point" virtues go, it's not all that great; probably would be worth (maybe) 4 or 5 points by itself. But pairing it with a -3 Major flaw means that it's really only worth 1 or 2 points in all...but it still costs 3. Some folks on the board would argue that it's not even a major virtue; and as such, as written it should actually be considered a minor Hermetic/Story flaw instead.
Magical Sensitivity is another. It's actually a decent virtue, in that it covers 2/3 of Intelligo Vim (ie, it doesn't cover spirits), but it's a Difficult ability, and it comes with its own flaw. (minor magical weakness.) I would say this one is actually fairly well balanced - it's just that there are other virtues that aren't as well balanced, (such as 2nd Sight, which covers the traditionally more-useful part of InVi, but has no associated Flaw) so PC's prefer those instead.