Yes, it does boil down to "it depends". Once a cadenza gets sufficiently long it isn't practical to keep the rule that an accidental continues until the next barline. It's usually better for the composer to put too many accidentals rather than too few, but you often come across cases where it isn't completely clear what was intended and it's up to you to make an intelligent decision based on what you know of harmony and style. An remember that composers and editors can and do make mistakes.
I just read through the version of this piece that is available on IMSLP. There are dotted barlines that can certainly be considered as normal barlines as far as accidentals go. There is also an obvious mistake: at the end of the cadenza, at the beginning of the last system on page 8, the first G in the right hand should be a G#, which is cancelled by the natural just before tempo primo.
Accidentals in cadenzas