Um...are we absolutely certain that 2.6k points generates a 1:30 wait time? Either I got lucky or the 1:30 ceiling might actually be lower.

No, those are values taken directly from the JP wiki. They are not 100% confirmed values as far as I know.

I could only go about starting to question it publicly after hitting that tier (monitoring the wait time especially) at least 50 times but part of me wants to consider the possibility that some of the past data may have failed to confirm the wait time and that the prizes received actually come from a different wait time and are being misreported

While misreporting is a possibility, I have not added anything to the table in first post without having been given a definitive wait time. Everything I add is based off the time waited and not the points value or the donation itself.