Uh, guessing you have never run an airline. But think about it…

If the published policy said they will put you on another airline, then the burden is on DL to find another airline going to that same destination with available seats in the same cabin.

-- What if there is no other airline going to the same destination?
-- What if that other airline wants to use those seats instead for their own IROPS pax?
-- What if that airline wants to hold seats back?
-- What if they refuse to sell them to DL?

What if DL said their policy is to never put pax on another airline? Unless every airline had a similar policy, DL would be shooting themselves in the foot. DL had said that their top 5% of fliers account for 26% of their revenue. Sometimes status talks and sometimes DL actually listens and goes outside the box.

Sure, we all like consistency, except when inconsistency benefits us. This is one area where no published policy works to the benefit of some at certain times.

Sorry about your grandmother’s ordeal but there is just not a one-size-fits-all for everything in the airline industry, much less something as unpredictable as IROPS.