As a biostatistician who's touched epidemiological studies, I'd argue losing the trust of participants and the public is one of the biggest threats to the viability of the whole research enterprise. It's reckless to jeopardize that as well. Conversely, this dataset will be mined for at least 30-50 years - there are an infinite number of questions that can be asked of this dat. Given that timescale, I think a little delay here is acceptable.