Cole/O'Reilly all came down to if O'Reilly had resigned or not with ROH. This result makes it obvious that he has not resigned as of yet.
There may also be an element of ROH sanctioning the switch on an NJPW show to demonstrate that such matches aren't simply filler where it is unlikely anything of note will happen, to better foster the relationship between the two companies. And where better to do it than at the biggest show of the year?
Wouldn't be surprised if a similar switch happens where an IWGP title changes hands on an ROH show in reciprocation this year. Unlikely to be the heavyweight title though. Maybe the IC at a stretch?
They kind of already did that with the TV title last year when Ishii beat Strong for the title during ROH's tour over there. Granted it was a smaller title and a ROH show so not the same effect. As for them doing the same with the IWGP titles in ROH I could easily see them switching one of the tag titles, especially the Jr. tag as it's seemingly always on foreigners.