This can be deduced from yesterday's Reuters article I linked which said the first reported death globally was in the UK (not South Africa) and from the fact that the study looked at 78,000 cases of Omicron from 15 November 2021 to 7 December 2021 (source: https://www.discovery.co.za/corporate/news-room). At the time the Reuters article was published we were 6 days after even the most recently reported of those South African cases.
I wasn't trying to present the global denominator - that is far higher than 78,000 since it includes all countries, not just the 78k reported in the South African country.