Papal visits to the United States have fairly long intervals to begin with. Wikipedia reports 10 trips between 1965 and 2015 (https://en.wikipedia.org/wiki/Papal_visits_to_the_United_Sta...). Given the relative rarity of visits, not having planned a trip during any given presidency would even be normal. It doesn't surprise me at all.

That's still a good question, though. Do any of them have anything more substantial than 'anonymous' sources, or even their own anonymous sources not linked to the breaking article's?

I am generally suspicious when anonymous sources quoted these days, but I am rather more suspicious of reports that only come from a single source and get repeated in multiple outlets more or less immediately.

I know there is some amount of synchronicity induced by syndicated news feed outlets like AP, but like many single source/anonymous stories, this reads to me like some 'suggested copy' was sent out to some reporters or outlets ahead of time.

Anonymous sources are important for the integrity of reporting, but it must also be recognized that they are essentially non-authenticatable information.

The author of the secondary source I see most mainstream sources quoting (Mattia Ferraresi) has also come out and said people are stretching and misrepresenting what he wrote: https://xcancel.com/mattiaferraresi/status/20424925662396866...

There is at least one outlet that appears to have asked the both Pentagon and the Church what was up and both parties told them the meeting was overstated as well: https://www.pillarcatholic.com/p/nuncios-pentagon-meeting-wa...