When the Pennsy couldn't find a taker for the LV it moved to cut costs by sharing facilities where possible; while they had to apply for trackage rights to serve Rochester via the LV from Buffalo, every indication I've seen was it was little more than a formality at that point.
Similarly, after the PC merger the LV was able to do away with duplicate track from Geneva to Auburn.
I'd have to look at a map of the PRR and the abandonment dates, but once PRR became PC, if that track still connected to the NYC somewhere it was one railroad and new trackage rights wouldn't be needed; the pre-merger rights would just be a formality to abandon.
Similarly, after the PC merger the LV was able to do away with duplicate track from Geneva to Auburn.
I'd have to look at a map of the PRR and the abandonment dates, but once PRR became PC, if that track still connected to the NYC somewhere it was one railroad and new trackage rights wouldn't be needed; the pre-merger rights would just be a formality to abandon.