Not mentioned is one of the side reasons for hold up on recognition. Namely that
Victor Ninov, a member of the team that first observed 112 was later implicated in producing fraudulent data at Berkeley leading to erroneous claims that the Berkeley team had observed 118 and 116. This caused them to look at the data on 112 again and they found altered records there as well though some observations withstood scrutiny.
But that put a bit more extra scrutiny into reproducing the observations. It was quite a little academic scandal at the time.