IIRC, there were two groups of groups working on it (the process was simple enough that a description from the press conference was enough to get started):

* people looking for fusion neutrons, who did not have much experience with the finickiness of neutron detectors and who reported seeing them when they were getting experimental errors, and

* people looking for excess heat, which was simply inherently difficult to measure accurately.

On the other hand, there wasn't a publication delay for the negative reports; within a week the groups started talking to each other and realized they weren't unique in not finding anything.