The story also goes on to say about how the deaths caused by the soviet-era disaster cause is disputed. How is that a pertinent thing to add?

It’s not disputed those are just different parts of the same IAEA report. 2 people died in the explosion, 28 of radiation poisoning, 1 from a heart attack, so 31 known, then 19 with high radiation exposure died years later for ambiguous reasons, so 50 potential direct accident deaths. And then they estimated about 4,000 as the total eventual cancer deaths.